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USA doesn't need hypersonic missiles because we're pretty confident we can pierce Chinese missile defenses with F35 or other such weapons.

China needs hypersonic because US AEGIS Cruisers are the best anti-air defense in the world, so China needs the best missile in the world to threaten them (As well as the Supercarriers that they protect).

It makes no sense for USA to build hypersonic, because none of our foes are building a missile shield comparable to AEGIS. Its the whole "Unbreakable shield / irresistible spear" paradox. If no one else has an unbreakable shield, there's no point making an irresistible spear.

> It makes no sense for USA to build hypersonic, because none of our foes are building a missile shield comparable to AEGIS.

If I remember right, one US General did come out and seem to be pretty worried about these hypersonic missiles and how far behind the US was in comparison. The Titanic was the 'unsinkable ship'. If the unbreakable shield breaks, you're going to want your spears to be the same strength as your opponents.

> you're going to want your spears to be the same strength as your opponents.

Why?

A substantial portion of energy in a Hypersonic missile is spent battling drag. Its far more efficient to kill them with sub-sonic missiles or supersonic missiles so that there's less drag. The less drag you have, the bigger the payload you can put.

Think of it this way: 100% of the weight of your missile needs to be allocated between thrust and explosives.

If you go 80% thrust, you'll reach hypersonic, but now you barely have any explosives left over. And the vast majority of this "thrust" is wasted on air-drag.

If you go 20% thrust, you'll have 80% explosives left over for your weight. You'll take longer to get there, but supersonic (and subsonic) has significant efficiency gains.

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There is a USA hypersonic missile project that does away with this problem by being 100% thrust and attacking with kinetic energy alone. But you can see... this fundamental physics question of allocating "explosive" vs "thrust" is very fundamental to the situation at hand.

I posit that any hypersonic missile will do less damage than an equivalent subsonic cruise missile of the same weight class. Because air-drag at hypersonic speeds really is a major play on the amount of energy you deliver to the opponent.

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You go "faster' not because it does more damage. You go 'faster' because it avoids the enemy defenses. But that speed costs you rocket fuel (rocket fuel that could have been high explosives instead).

Well my thinking is that if your missile shield is broken, your fleet is now vulnerable and are likely to get destroyed and you're also vulnerable to an attack on home soil. If you can't get your boats across the ocean how can you ship supplies across the ocean to troops that are on the ground? How can you defend yourself from attacks on home soil if the missiles can penetrate your air defences and fly faster than anything you can send after them?

That's called a Ballistic missile and those are just how nuclear war works.

The general assumption is that no one uses nukes. Because if we go nuclear, the world as we know it is over.

There is no missile shield vs Ballistic missiles or ICBMs. That's always been true. Our defense against ICBMs is always the same, we have more of them and promise to blow the enemy up with our more numerous, bigger nukes.

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The reason hypersonic missiles are a 'thing' is because they aren't nukes. They work because China (presumably) figured out a homing device that can lock onto ships.

So from a conventional perspective, it's about hitting a fleet of ships without escalating to nuclear combat.

That doesn't mean that China instantly wins vs Taiwan, it just means we need to be careful about our fleet positioning and stay outside of China's sensor / homing mechanisms range. Our F35 can perform mid-air refueling for a reason, we can sit outside the range of the Chinese missile and still fly missions, albeit with a slower response time due to the increased flight distance before combat.

America is way too close to Taiwan with their bases in the ryukyus. They aren't technically in Taiwan, but any attack will involve them pretty quickly. Likewise, America stationed troops on the border of ROK and DPRK to act as a deadman switch. Those troops are quickly toast if any fighting breaks out, but it would ensure America's involvement in the successive war to come. Anyways, the USA's involvement in a war with China or North Korea via Taiwan or ROK is pretty much guaranteed.

I agree. It's not just that though, part of what gives the powerful country it's power is the belief from other countries that they won't back down when an aggressor comes knocking. The US can't really not get involved because even not getting involved is a sign of weakness/defeat. Dalio mentions this a bit in the video in the original comment.

The question it comes down to is how many fronts can they effectively fight on? If the US is fighting in the Ukraine trenches, the Taiwan strait and the Korean border, how much do they have left over for the other places? Even stuff we take for granted such as shipping goods around the world easily because of the general lack of piracy goes out of the window because you need the warships that were policing the shipping routes for the war effort.

The USA is resourced and practices to fight around two wars at the same time. With Russia being almost spent just fighting the Ukrainians and North Korea being basically bankrupt (while both South Korea and Japan are not slouches militarily), the USA will be fine.

But how much debt would it be in at the end of it all and is it still going to be able to maintain it's status as the dominant power? If all this happened, my money would be on India leapfrogging to first place because it would be able to stay out of the main conflicts whilst simultaneously being able to leverage it's massive population and engineering skills to become the biggest manufacturing force.

As soon as India see China is loosing they will likely use that to settle all the open territorial disputes quickly.

The US winning just cements the dollar dominance in the world.

> As soon as India see China is loosing they will likely use that to settle all the open territorial disputes quickly.

This has fairly similar parallels to what happened in WW2 though. US entered the war mid way through after Pearl Harbour and helped win the war, theoretically India could do the same.

> The US winning just cements the dollar dominance in the world.

Again, in WW2 the UK was the dominant currency, was on the winning team, but lost dominant currency status because the debts amassed were too large that it no longer had enough money to maintain the infrastructure necessary and service the debt so other countries sold off their holdings of GBP debt in favour of the safer haven of the US.

The UK was in pretty bad shape after WW2, and accelerated dismantling its empire (so it was mostly gone by 1949). The US never had an empire to begin with, and was relatively untouched by WW2. They lent a lot of money to help Europe and Japan rebuild, the rest is history.

The US doesn't have a traditional empire but it does spend a lot of money on international military bases as well as protecting strategic infrastructure and resources across the globe.

It's difficult, if not impossible, to maintain that kind of global influence and service stratospherically high debts simultaneously. In that scenario, spending money to resolve internal problems always ends up taking precedent over global influence and other countries with rising bank balances step in to fill the void.

> But how much debt would it be in at the end of it all and is it still going to be able to maintain it's status as the dominant power?

Whatever it takes? As long as American interests are threatened. I don't mean jumping into every single quagmire of questionable value to the USA (Afghanistan, Iraq, Vietnam), but if Taiwan, Japan, South Korea, Ukraine were threatened with being taken over by..actually anyone at all...I don't see how the USA couldn't get involved, and why it wouldn't be in their interests not to.

The alternative is a rapid decline in world stability, which would cost way more than whatever America spent fighting instead.

> If all this happened, my money would be on India leapfrogging to first place because it would be able to stay out of the main conflicts whilst simultaneously being able to leverage it's massive population and engineering skills to become the biggest manufacturing force.

If India were able to function and produce at America's level, they would already be leapfrogging everyone, but they are still pretty dysfunctional in terms of governance and allocating capital and labor productively. The only part of India doing well is a small private sector in technology that benefits from the government not caring about it enough to meddle.

China, on the other hand, has a much better chance of capitalizing on American instability one way or the other IF they are somehow not involved in the conflict.

> Whatever it takes?

Yes but this is what the UK did in WW2 and ended up with so much debt that it could no longer service them and other countries lost faith in buying the debt and so they invested in the US instead.

> If India were able to function and produce at America's level, they would already be leapfrogging everyone, but they are still pretty dysfunctional in terms of governance and allocating capital and labor productively. The only part of India doing well is a small private sector in technology that benefits from the government not caring about it enough to meddle.

They're growing rapidly and they're one of only four countries to put a vehicle on the Moon. If the world was at war there would be a lot of money to be made and they're one of the only countries that would be well positioned to take advantage of it.

> China, on the other hand, has a much better chance of capitalizing on American instability one way or the other IF they are somehow not involved in the conflict.

Well yeah, but we're specifically discussing a theoretical conflict in which they're one of the main players in the conflict.

> They're growing rapidly and they're one of only four countries to put a vehicle on the Moon. If the world was at war there would be a lot of money to be made and they're one of the only countries that would be well positioned to take advantage of it.

India is probably about where China was I would say 25 years ago (having visited China in 1999 and comparing it against what I saw in India in 2013 or so). There is a lot of documentation about visiting the moon, and while an accomplishment, and probably something that should be done along the way to development (especially if you want to launch like ICBMs, which was the main product of America's moon program), its a bonus. But it isn't as great as figuring out how to do it from zero. Keep in mind that even China lags on jet turbine and semiconductor production (they can get either good perf or good costs, but not both at the same time), that just means India has another 30-40 years before it catches up with the US (assuming the US stagnates, which is probably a good bet).

> The USA is resourced and practices to fight around two wars at the same time.

No, its not, and arguably it never was. The two major regional contingency concept was adopted shortly after the first Gulf War and was an organizing principal in theory for a couple decades, did not actually provide the capacity to succeed in two major regional contingencies simultaneously [0] the only time tested, and has been effectively abandoned.

[0] there's no particular resourcing need for any number of contingencies of a particular scale if you don’t demand capacity to win.

The DoD plans for fighting 2 major conflicts at the same time and always has.

China has more ships by count and it means zero. Coastal and patrol boats mean nothing.

At the end combine combat arms win the day and there is zero indication that China has sorted that. Heck, I would offer that with their top down structure they never will. Let us not forget in the US military a PFC is taught how to and can call for fire support. You have to be an officer to do that if you are russia or China.

The largest air force in the world is the US Air Force. The 2nd largest, the US Navy and the 3rd, the US Army.

In Ukraine the combine arms concept even without an Air Force that owns the sky is tearing apart what was the 2nd largest military in the world. In a full out war with China the US would own the sky battle space pretty quickly.

I am not saying that China will not sort this at some point, but right now they are looking at Ukraine and going "hum".

Taiwan is a fortress and as long as the people of Taiwan are willing to fight it will be a near impossible nut for China to crack.

Another note is how dependent China is on oil imports. The US could quickly blockade all imports pretty quickly far from the range of land based Chinese missiles. They would be out of oil in 2 weeks. That part of the world has a very defined set of choke points.

I agree the US military still has a lot of significant advantages and that Taiwan would be difficult to take. I disagree that oil would be a major factor because China would just pipe it in from Russia.

A pipeline is an easy fixed target. In a war the US will want to it to end quickly so cutting off the oil will be an easy choice.

https://warsawinstitute.org/china-malacca-dilemma/

That link seems to be about sea routes. I’m talking about a pipeline or most likely multiple pipelines that would be skirting around Mongolia. You’d have to do either a lot of dogfighting to get there if you’re using planes or hope you can get a missile or drone through. A HALO jump sabotage mission would also be super difficult.

China’s critical infrastructure is too concentrated. The CCP won’t survive a bombing campaign since its legitimacy comes from economic development.

I don't know much about Chinese critical infrastructure. I would however say, that if a bombing campaign on home soil starts anywhere in the world, it is pretty easy to leverage that into a united front. If people start losing fathers, mothers, sons and daughters they tend to want blood in return, at least until they're tired of war, and they'll support whoever gives it to them.

There's also just general balance of attrition to consider. PRC with 4x population has 3-4x more infra to hit, and homeland strikes will beget homeland strikes - PRC conventional icbms can take out US refineries and revert everyone to Yemen. Reality is US gained resource autarky but lost resource security since advanced rocketry now makes CONUS vunerable in peer war. PRC having more of everything, and hence more room to weather infra attrition, and ultimately still a massive/excessive construction industry to rebuild faster. PRC generally stuck with surplus of trained workers due to overcapacity. Meanwhile, US is much more vunerable to disruption of homeland serenity - hard to import talent, maintain global finance system, tech dominance if US has no power, fertilizer inputs, data centres. Ultimately, homeland strikes might be short term pyrrhic for everyone but medium/long term trajectory, it also matters who has capacity to recover, and who has more to lose by having homeland degraded in first place.