It is not that hard.
Dems are drinking from the same trough as Trump.
If Dems attack Trump (and his children/associates) for criminal financial dealings a Pandora's Box of shady financial dealings (for both parties) will be exposed for all to see.
Until the American people stop turning a blind eye to the shady dealings of their own party (team) our nation will never be able to effectively address political corruption.
Dealing with political corruption should not be an either or proposition.
BOTH Trump and Biden can be held (and should be) accountable for their (and their families) shady behavior.