Once again – this time in a matter of life and death – President Barack Obama has thumbed his nose at Congress. Many members, both Democrat and Republican, are angry.

This time, Obama agreed to trade five high-ranking Taliban terrorists for an American soldier who walked away from his post in Afghanistan and was taken prisoner by the Taliban. Obama did so without notifying Congress, as required by law.

Many are worried that by freeing Taliban leaders, Obama has jeopardized the lives of U.S. troops still serving in Afghanistan.

But the president’s refusal to obey the law on notifying Congress already is a fact. It is just the most recent entry on a long list of refusals to stay within constitutional limits.

Yet some in Congress continue to let him off the hook. What will it take for them to comprehend this is not a matter of politics, but one of preserving our system of government?