This is a fundamental misunderstanding of the American system of government. Unfortunately due to the flaws in our constitution it's functionally impossible.

You'd have to get the majority of Americans to support reform. Which will be hard, but not impossible. Now you can try to make it a law. If the Supreme Court rejects that law based on the constitution then you have to wait. The movement would have to continue for decades waiting for Supreme Court justices to die or retire until newly appointed judges that support the law are appointed. This is a long time for a movement to sustain power. Alternatively you can have 2/3rds of congress or 2/3rds of states make an amendment to the constitution. That would be nearly impossible.

This system is actually what makes Trump so dangerous right now. He basically controls Congress and the Supreme Court giving him a blank check to violate the law.

Talk about a flawed system