Some of the powers delegated to the Congress include providing for the general welfare and common defense. If those are threatened, Congress in empowered to act by the necesary and proper clause.
The sesesh thought they could get their way with little or no fighting. They didn't listen to Sam Houston:
"Let me tell you what is coming. After the sacrifice of countless millions of treasure and hundreds of thousands of lives you may win Southern independence, but I doubt it. The North is determined to preserve this Union. They are not a fiery, impulsive people as you are, for they live in colder climates. But when they begin to move in a given direction, they move with the steady momentum and perseverance of a mighty avalanche."
There is no way out of the Constitution except through amendent or revolution. That was the intent of the Framers. They had seen the Articles of Confederation fail. They didn't want that again.
Walt
But what happens if government uses its power to infringe upon or even destroy people's rights, as our Founders feared it might do? As the Declaration points out, in that case it is the right of the people to alter or abolish their government and to institute new government that would be more likely to protect their rights.
What rights were being infringed upon?