That's worked out well everywhere it's been tried. Not.
Ultimately it may take a number of measures to keep government in check. Ultimately it is the people and their force of arms which will keep government in check. Certainly the SCOTUS wont do it.
Goodness knows, our current court system is extremely far from perfect, but it's better than no court system at all. "The people" do not agree on the meaning of the Constitution, and the central cities are as well-armed as the heartland. Are we to decide every constitutional question by shoot-outs in the streets? I'll take Chief Justice Roberts over that system.
Military power is the only way marxists are ever thrown out of office. Either by its use to stop marxist military advance, societal collapse where the military refuses to maintain the marxists in power, or removing them. From power and restoring freedom to people. Is there risk ? Of course. But actually it has worked well where it has been tried. Chile comes to mind.