Because Costa Rica has agreed to act as a client state of the US and is protected as long as they do what the US government says.

> Using this logic, why don’t more countries attack, say Costa Rica, which doesn’t even have a military?

You might want to read up on the "Inter-American Treaty of Reciprocal Assistance". Essentially, "the rest of the Americas".

That mostly works because the set of potential aggressors is small. (Nicaragua and Panama). OK, fine, the US might want to, but they're close enough partners that they don't need to.

> they're close enough partners that they don't need to

I think that might be the crux of what GP was getting at. There's more to it than the ability to win (and in a hopeful dreamy world, I'd wish we can all get to the state where collaboration is always the obvious better choice, but that's obviously at least a few hundred years off... something to strive for, though)

To the US, "winning" is basically defined as having access to local resources (including workers) at market rates without the responsibility of governing.

AKA -- free trade. Global free trade exists because the US wants it to. In that sense, it's currently winning/won. The size of the US military and economy (and it's close allies) are largely what enforces that world order.

Personally, I think it's better than the old model of imperialism (it's certainly way less violent and has rapidly increased living standards across the globe). But it's still a case of the big powerful countries enforcing their will on smaller countries.

Free trade lives on the back of enormous military spending. Particularly commercial shipping lanes are protected by the power of the US Navy.

The past few years have seem drastically reduced US Naval spending, particularly on the protection of commercial shipping (the shipping and military news sites are almost ready to agree that the US Navy has abandoned this part of the mission entirely). Under Obama's administration we balked at protecting the commercial fishing rights of our allies in the Philippines and it's expected that this kind of policy in reaction to Chinese aggression in SEA will continue.

Then COVID hit us and we might actually see a real unravelling or the last 60 years of global economic policy.

This means that we should probably expect more conflict rather than less.

> why don’t more countries attack, say Costa Rica, which doesn’t even have a military?

Because of the Monroe Doctrine [1], which has been applied in some form or another for the past couple of hundred years.

[1] https://en.wikipedia.org/wiki/Monroe_Doctrine

> "This makes no sense. Using this logic" ...

I was almost-directly quoting the co-founder of Anduril.