Globally we spend trillions on weapons (specifically nuclear weapons) that nobody wants to use so the problem doesn't seem completely insurmountable?
As a well-known example, modern trauma medicine was practically invented by the US Army. They systematically invested in research for the better part of a century to maximize survival rates, minimize recovery times, and restore full body function post-trauma to the extent possible. If you are in a serious car crash, most of the procedures to optimize your outcome were originally developed in a battlefield context by the military.
They also fund a lot of research for relatively common diseases that attract little government funding otherwise due to lack of fashionability e.g. multiple sclerosis. Their incentives are different than either the rest of government or the private sector, and that is probably a good thing.
The one exception is “national security”. So military spending is the most efficient to create jobs in the US because you can prevent hiring in other countries.
An example in the opposite direction is US subsidies for solar energy. These subsidies do create some jobs installing them, but the majority of jobs end up created overseas in other countries like China.
If we were to be constrained by WTO rules (an organisation hardcore Leavers seem very fond of) perhaps we can expect an increase in UK arms spending, though this being the UK no doubt this won't mean any improvements for the people at the sharp end of things.
I dare say defence procurement will be similar.
Here's to cutting all that contracting red-tape the EU had us wade through. /s
The political contributions of the sheet metal shop in your district that stamps some widget for the F-35 at 50x market price definitely matter.
Right after "common defence" comes "general warfare" but for some reason that's something most Americans (or at least their politicians) seem to prefer to ignore.
I think it's pretty obvious that the narrow view is the only defensible one.
However two things seem clear to me.
1) In practice in the US today the "general welfare" clause is interpreted expansively when it suits the purposes of the politicians. This is also supported by the article you link: "To date, the Hamiltonian view of the General Welfare Clause predominates in case law. ".
2) I think that most people throughout the developed world believe that ensuring the general welfare of a country's citizens is an essential function of government. Outside of the US, especially in Europe and democratic Asia this is probably an extremely dominant view. In the US you hear a lot of very vocal people, apparently such as yourself, argue against it, but I think that's a minority view even here.
State governments are sovereign, too, and have far fewer constitutional restrictions on what they may do. I may not agree with the social-welfare schemes dreamt up by Texans, Michiganders or Californians, but they do not effect me, so it's not really my business. OTOH a federal social-welfare scheme effects me and is patently unconstitutional.
The DoD is partnering with (funding) phage therapy research companies.
http://www.theshadowworldbook.com/
Mind you - not a book for the easily angered.
Since the development of nuclear weapons, there's been no outright wars between the major powers for nearly a century. We've lived through the most peaceful period in all of human history. It's debatable how much nuclear armarment contributed to that. But prima facie, it certainly seems like a major reason that the US, Russia, or China haven't gone to war with each other.
Given the carnage of the previous two world wars, it seems to me that every dollar spent on nuclear weapons was worth it ten times over.
BARDA [1] has a defence mandate, though it reports to HHS, and is a major public funder of antibiotic research (per the article).