IBM and General Motors can’t deny citizens their right to a trial by a jury of their peers, only government can and does that routinely. All the corporations in the Fortune 500 can’t kick in my door in the middle of the night based on some anonymous tip; government agents can.
Who passed Jim Crow laws? Government. Who passed anti-Chinese laws? Who turned their collective heads and refused to enforce the laws once racial discrimination became unlawful? Government. Who uses racial profiling to stop people for “driving while black?” Government. Who broke countless treaties with American Indians? Government. And who is even now ignoring numerous Constitutional restrictions? Government.