The Russians are undoubtedly in the moral wrong in this war. Not every wrong can or should be righted by the US military, though. And you are correct that are many instances of US politicians promoting lies to fund endless wars under false pretenses (Vietnam, Afghanistan, and Iraq). Sadly only two modern US presidents kept the US out of wars (Eisenhower getting us out of Korea and Trump laying the policy groundwork to end the endless war in Afghanistan). It is overstatement, however, to suggest that the US military. has never done any good. The US did provide substantial support to Russia during WWII (and Russia was arguably as bad as Germany in that it invaded Poland as well in 1939 and committed all manner of atrocities). The US military did liberate western Europe from the Nazis and provide a buffer from future Communist aggression. Defeating the Japanese in the Pacific and Asia laid the groundwork to end decades of colonization and abuse of those regions by Europe and others.
We won WWII with the help of the Soviets who lost over 20 million people in the war. The Soviets helped on Pacific front too along with Mao's China.
We created a buffer in eastern Europe and beat the Soviets to the moon with the help of former Nazis.
We won the Cold War (against the Soviets) with the help of Communist China.
We helped Islamic extremists (who later created Al Qaeda and the Taliban) drive the Soviets out of Afghanistan.
In Libya and Syria, we backed Islamic extremists in their attempts to overthrow secular Arab dictators.
Since 2014 in Ukraine, we've helped Ukraine, one of the most corrupt countries in Europe (and the world), counter Russia's attacks on their national sovereignty.
I raise these examples to make the point that this stuff in America's recent history isn't always morally clear or Black and White. Often times, our leaders have collaborated with bad guys to take down other bad guys. And often times, there have been unintended consequences of our policies.
