You know what's a tragic waste for me? Most of the US military budget, its spending on the War on Drugs, its tax cuts to billionaires and corporate welfare.
Let's cut those in half and talk again about SETI, which I would be happy to fund a hundred times over if it meant less killing, fewer unjust incarcerations for victimless crimes, more economic equality, and less concentration of money and power in the hands of the elites.
I think it isn't so easy to say that what the US military does is a waste of your money. A lot of US foreign policy is about "free trade" that's beneficial to the US. If you were to cut off the US military then you'd likely have consequences for global trade. Perhaps you're right that it's a waste of your money, but I think that this is not at all a straightforward conclusion.
Eg imagine if Iran just decided to stop oil shipments through the Strait of Hormuz with their military. How would you deal with this without a sizable military yourself?
Edit: or imagine that some country decides that they don't like goods related to the US going through Panama so they decide to occupy it. It's not US territory, but the loss of that will harm the US economy.
The Iranian navy is mostly famous for its usage of rubber dinghies. That's not a serious threat that needs 10 supercarriers to counter. If they decided to change that, then no problem, nobody wants the strait blocked so it will be easy to find allies to pressure the iranians into a deal. The panama canal doesn't need that either. It should be in range of US based aircraft. Current US spending can only be justified by pursuing multiyear wars, occupation of territory halfway around the world, complete domination of the seas, the ability to fight a war on two fronts (and win), the ability to obliterate earth ten times over and guarding others borders (thanks, by the way). I'd say a military the size of spain's would be sufficient given a more basic definition of security needs.
It’s not clear the force size you suggest would result in a stable equilibrium. You’re missing one key justification: the ability to dissuade future military competition. A defense force the size of Spain’s would face substantially more threats given the value of US targets and interests, so we’d then need to increase spending. It’s hard to predict what that world would look like. In the past it wasn’t great. Outspending everybody else from the get-go works.
And the UK can do that because the UK is willing to rely on the US. Now that relations with the US are straining in the West other western countries are increasing their military spending/cooperation. (Eg EU army.)
Sorry, but according to news sources a coalition of non-US vessels are doing the bulk of patrols out there in the strait of Hormuz whilst the US is only seemingly wanting to lend 'command and control' style support.
Elsewhere the UK assists the US in Syria and Afghanistan. It's not the other way around.
But feel free to tell me how great the american way of doing things is. What with fantastic provision of basic healthcare for its citizens, and sensible gun control oh yes and affordable education.
It's not about who patrols the Strait of Hormuz. It's about who and what backs them up. If the Iranians decide to sink the frigates there (to do their blockade) then they can expect a visit from a US carrier group. If there is no force that can be projected there then it becomes about who can move more stuff there. Seeing as that's literally next to Iran, Iran is going to win.
Look at Crimea if you want an example of what can happen if there's no force that can back you up.
The Cold War was essentially about trade. And it's not that Iran would stop all oil shipments forever. They'd stop some shipments that are related to certain countries that they don't like as a political move.
Let's cut those in half and talk again about SETI, which I would be happy to fund a hundred times over if it meant less killing, fewer unjust incarcerations for victimless crimes, more economic equality, and less concentration of money and power in the hands of the elites.