The fact that America buys Iraqi oil didn't prevent it from being bombed back by decades.
This seems to be people ruing that our project to dominate the entire world with an ideology that had us comfortably in charge is failing.
Obviously, trade between a hegemon and a small country isn't going to deter wars of imperialism. Because the hegemon can force the trade relationship.
But it should deter war between the US and China. China's leaders want to survive. If they stop the gravy train of trade, they're putting their own survival at risk.
The Iraq war wasn't 4D chess it was much worse: Americans really believed in it. Which is ultimately also why they got their ass kicked: free elections were held and the Iraqis wanted the Americans out. Instead of installing a puppet government what they got was Iraqi politicians with agency.
Until they wanted us back to fight Daesh.
In any case, the GoJ is keen for us to leave as well, and we probably will soon, but that doesn't make Japan our enemy or mean that we "got our asses kicked" in WWII.
This is an interesting take - I don't think the goal at the start of the war was to install a puppet government; it was to dismantle the government in power and prevent whatever took its place from having any real ability to project power against vital US interests. Both of these goals were accomplished.
We should not get wedded to a particular prism. They're all partly true.
Trade and treaties deter war to an extent (liberalism). Nationalism can sometimes be a major factor as in Iraq 2003 (constructivism). And sometimes it's actually about defense concerns, e.g. the Soviet-Finnish Winter War (realism). These are all partly true theories.
Just like Baltic states few months later.
Of course, we're reading his mind here, so it's hard to say for sure.
I didn't study Stalin's proposal to Finland that much, but essentially it was same deal as for other Baltic states. Take our military bases for „defence“ and we may sweeten the deal a little bit with a gift. Because who cares if we're going to annex you next summer one way or another :) Couldn't do that in 1920, but USSR thought it's strong enough in 1939.
For example Lithuania and Vilnius case. Well, so nice of him to give back historical capital, isn't it :) Just to use sweeten the deal of installing army bases in Lithuania-proper and then using them to annex the whole country next summer.