Biden surrounded by "straight up Marxists" - not really. A lot of progressives and so-called liberals have been captured by *some* Marxist/postmodern/poststructuralist ideals such as equality of outcome, but not all of them.
Attempts to get them out seen as "violent attack" - definitely not. They would not resist a democratic mandate.
There is plenty of ground on which conservatives and progressives can agree. Use that as a basis to clear out extremists and extreme ideologies rather than trying to draw a line down the middle and provoke culture wars more.