They have been known to deny the freedoms of speech and assembly, the right to equal protection of the law and the ability to bring suit against powerful interests. They continue to suppress the vote.
Our federal courts were created to safeguard against those abuses. They are the conscience that helps us see our errors and mend our ways.
A president who is contemptuous of that judicial responsibility, who spends nights questioning the honesty of federal judges who find against him, trying to undermine confidence that they are fit to hold office, that president weakens our freedoms.
Our Founding Fathers knew there would be bad actors among us so they set up the Judicial Branch in a way that would make it immune to tweets. Federal judges, you see, are appointed for life. [Article III]