Earlier quoted context omitted.
It's not (just) about overkill. Nobody else underwrites global free trade, and that's incredibly expensive: https://news.ycombinator.com/item?id=23434640
This argument dissolves under even the lightest scrutiny. Let's assume for a second that there is a dollar amount to "underwriting global free trade" (spurious to begin with). What actually is that dollar amount? Is it 3x more than what we're spending? 10x less? How could we ever know? As it turns out, whatever we are currently spending, that's the amount required. We could double the number of aircraft carriers, nuc…
Setting that aside, to put it in HN terms: imagine nontechnical people at your company comparing the wildly disproportionate relative costs of two IT projects, but without comparing the relative scopes of said projects. That would make for a poor foundation from which to either justify or criticize existing budget allocations.
That's what happens on HN every single time the subject arises.
'American military budgets are bigger than everyone else's' ergo 'American military budgets are far too big.' But it doesn't logically follow.
Power projection is exponentially more difficult and complex than homeland defense.
Yes, there's waste, and yes, it could be run more efficiently and at a lower cost, but it's worth noting that the other points of comparison (other nations) also contain no shortage of waste, and in some cases proportionally more. And slashing overhead to the absolute bare minimum possible is not the kind of risk management one would prioritize first in a system with an incredibly damaging failure state. (Disclaimer so it's more difficult to misstate my position: I believe that waste that is illegal should be punished criminally, and all other bad-faith waste that is political should be punished politically, and we should consider enacting laws to make such bad-faith waste illegal.)
Meaningful conclusions can't be reached by virtue of looking at relative costs while wrongly assuming you have a working knowledge of what they respectively achieve. This is what non-technical people do to technical people all the time, HN laments it, and then turns around and does it in many other spheres.
The military budgets of most nations are to provide some degree of homeland security, sometimes a little regional policing, and sometimes whatever extra is required to satisfy the political needs of their alliance leader. And tthat's about it.
Nobody else comes remotely close to being able to guarantee that an oil tanker can transit the Strait of Hormuz and sell barrels across the globe to multiple nations which have hated each other for centuries (or longer), and worse: to multiple nations which have competing and conflicting geopolitical imperatives. And it's not just oil, this applies to virtually all (non-sanctioned) nations and goods that aren't manufactured in their nation of consumption, using domestically-sourced materials and processes.
It simply isn't comparable.
It's worth remembering what the world looked like when countries which depended heavily on raw materials and trade developed their military capabilities precisely to secure those things, because without it their survival was in jeopardy. When a nation depends on those things for mere survival, its use of force doctrines eventually evolve resemble those of a cornered animal.
With the notable (and now obsolete) exception of securing an oil supply and the thread of the Soviet Union, the US does not depend on anyone else for its survival.
I think that we have a lot of people either unaware of how things worked prior to 1944, or holding the mistaken assumption that the underpinnings of our global framework exist either by happenstance or as the result of some kind of global enlightenment, as if human nature has finally changed for once.
There's also an implicit assumption made that one merely spends more money to beat other countries at shooting wars, countries which spent less and were therefore ill-equipped to compete. That assumption is reasonable in that it's based on millennia of recorded history, but faulty in that it ignores how the world has worked since 1944.
Yes, the United States has required countries to develop their military capacity sufficient to alleviate relatively minor regional issues (e.g., JSDF), or to create a shared purpose (e.g., NATO), but for the last ~77 years the United States has almost single-handedly created the conditions in which global free trade has been achieved for the first time ever, and the military has been central to imposing the conditions necessary to achieve it.
And before anyone asserts that pirates are a relic of centuries past, or that nations no longer desire to even engage in such tactics, this kind of thing regularly happens even under trade conditions imposed by the world's only superpower: