Yeah, it's common for many to assume Iranian aligned factions such as the Houthis or Hezbollah have no agency, motivations or origins of their own.
Also notice how dramatically they stepped up their campaign against KSA since Iran launched its aggressive campaign to lash out against economic sanctions.
There's no inherent reasons the Houthis should be launching sophisticated, high-impact attacks on KSA on a weekly basis. This sort of escalation makes no sense within their own geopolitical context, but makes perfect sense when you consider Iran's contexts and regional goals.
Same for Hezbollah group in Lebanon against Israel. All the recent tensions in that conflict can't be explained by the organic interests of the Lebanese nation or people. In fact, a conflict with Israel is against the Lebanese national interest and would lead to great destruction in Lebanon. However, Hezbollah is escalating and building up towards that very conflict.
The vast majority of Hezbollah's budget is contributed by Iran:
https://en.wikipedia.org/wiki/Funding_of_Hezbollah#Iran
Iran can ill afford to make that investment if they don't get much out of it, and it's pretty accurate to say Hezbollah is acting according to the interest of Iran far more than any other set of interests, including the Lebanese interest.
Hezbollah owes its power and arguably its existence to Iran. It's naive to expect it to act independently of Iranian interests.
Here's another article about their military activity in Iraq: https://en.wikipedia.org/wiki/Iranian_intervention_in_Iraq_(...
Besides that, they have been involved recently in multiple actions to seize oil tankers, culminating in the seizure of a British-flagged tanker:
https://www.nytimes.com/2019/07/20/world/middleeast/iran-tan...
They seized other tankers as well, for instance:
[1] Prisoners of Geography: Ten Maps That Tell You Everything You Need To Know About Global Politics
Many of these nations are now failed states, containing factions that are more powerful than any sort of central government or military. Chief examples of that are Hezbollah in Lebanon and the Houthis in Yemen.
However, there are ME nations-states that do have a strong and coherent central government. Egypt, KSA, and Iran are examples of that.
So a more accurate model would be a mixture of failed artificial states interacting with states that are more functional and coherent.
Without the Saudi intervention, the Houthis would most likely not have much of a relationship with Iran at all.
Either way, the KSA intervention failed, and the Houthis were able to take over and establish themselves as the dominant power in Yemen, so my assertion stand: they currently have no organic reason to launch a campaign against KSA. Normally a rebel force in this situation would focus on stabilizing their own rule in their country.
Also, the Houthis had launched around 200 previous drone attacks against Saudi in retaliation; this one was just significantly more successful, as opposed to a new campaign.
In 2015, when the Saudi’s intervened, a UN assessment asserted that there was no evidence of Iran having any “command and control” over the Houthis at the time.
If intervening in the Yemeni civil war on the side of a losing faction and bombing indiscriminately earned Saudi Arabia the Houthi’s enmity, pushed them closer to Iran, and resulted in an effective reprisal, the moral of the story would seem to be that actions have consequences and rashly attempting regional hegemony carries risk.
The rest of your comments don't contradict my initial statements. The Saudis tried to keep Hadi in power and failed. The attacks against them by the Houthis are inversely correlated to the Saudi intervention. The Saudis have been scaling back their intervention, while the Houthis are attacking them more and using firepower and weapons they obviously received from Iran.
The Houthis have no reason to keep escalating against KSA now that KSA has virtually stopped their intervention. This would be an insane strategy - a rebel force launching extremely aggressive and escalating attacks against a large and powerful neighbor who stopped fighting them 3 years ago.
The only way you can explain this is that they are doing Iran's bidding. As the weapons are Iranian, this is hardly far-fetched.
As for the fantasy of Saudi Arabia stopping intervention, they bombed a Houthi site in Dhamar less than two weeks ago in continuation of their bombing campaign of the last four years. That attack, which killed around 100 people, was merely the deadliest in this extremely dirty conflict, and likely sparked the Houthi reprisal.