Also because it would be pointless.
The Democrats have been using Russia as a boogeyman to scare America’s vast supply of low-info dullards since Trump was elected.
Russia isn’t America’s enemy. America’s population of aging hippie Leftists, aided by their indoctrinated kids and grandkids, most definitely are.
They do need the boogie man for elections and riots
They want to criminalize dissent, and there's nothing like a war for doing that.