I think it has to do with the desire of war mongers/defense industry shrills to find their next enemy after the US was defeated in the middle east. First the evil empire was Russia, then it was radical islam. Now it's Russia again. It's big business, the past two decades cost the US tax payer many trillions of dollars.
The popular interest in making Russia the 'new generational enemy' started in 2014 with Crimea and seemed to escalate with Russian inference with the election of Trump, and Trump being a fan of Putin. Then the US withdrawal from Afghanistan took the middle east off the agenda.
The problem is, being into waging war against the middle east is one thing, screwing around with Russia- who is much more dangerous- is another. It's like playing with fire.
The odd part is the liberals are really getting into it.