IMO, partial blame on the Democratic Party for not successfully countering rightwing propaganda techniques and for executing some flawed policies; partial blame on citizens who chose not to vote or chose to protest vote against them; and mega huge absolute blame on the Republican Party for promulgating bigotry and lies and on their voters for not critically examining this disinfo, not having the heart to care about their fellow persons, believing that they must adhere to their in-group, and for also repeating the aforementioned disinfo and bigotry.

Each of these is a point of failure and must be remedied if we want to actually have a decent society to live in.