[shufflerofrocks]

>Sure, we've all studied the Mexican-American war (1846-1848)

and Cambodia, Iraq, Vietnam, Cuba, and 50 other known instances with more than a few of them in this decade itself.

Given how good the US is at the sort of foreign meddling, and that supporting protesters hasn't ever worked in reversing regime-change (unless it was an extremely unstable country), taking control of a territory that US is using for it's operations isn't an invalid move, geopolitically speaking.

>there's a "Russian River" in California just waiting for its own SMO: Славянка наша?

Lol. I'm not at all disagreeing with the ideological basis in your point, but Russia's wanted Ukraine for a long time, and US using Ukraine as a frontline provided a convenient excuse.