You don't need to go super far left to find convincing arguments against US foreign policy. Noam Chomsky is a mainstream intellectual after all, and he coined the phrase "consent manufacturing".

The idea that the US acts in total self interest should be presumed true in all cases, but that doesn't on its own defeat the idea that its intervention in Ukraine is good. The logical next step is to ask ourselves whether this intervention ever had any chance of changing the outcome of the conflict at all. If it didn't, and most people here would agree that it didn't, then the US' involvement amounts to wartime profiteering at the cost of human lives.

edit: I should also add, there's good reason to believe that NATO expansion is what caused the conflict, and that the west did this in spite of clear and explicit warnings from Russia

neutral on politics

Yeah... About that. There is no neutrality in politics.

Why don't you go look up what the US and Saudi did to Yemen over the last decade and decide how you feel about sitting on that fence.

Go beat up the Russian military because they're the bad guys and our cost is super low.

They're not beating up the Russian military. They're fertilizing the fields of Ukraine that the Rada is going to sell to Blackrock. There's nothing noble about this. NATO pushed and pushed and pushed until the RF took the bait, and now they're bleeding the RF using Ukrainians because they don't give a shit about Ukrainians. Christ this is so frustrating ISTG if people would just read Sun Tzu they'd understand everything and we wouldn't need to have these absurd conversations over and over.