Should the US constitution be dissolved in an emergency situation?

Should the US President be granted dictatorial powers, or all governing decisions be given to the military during a national emergency? There are still checks and balances embedded in the constitution during situations when an emergency has been declared to help maintain some political power to each branch of the government, and help ensure a declaration of emergency isn't prolonged for political purposes, or to ensure there is actually a situation that constitutes a disaster. It is said that Abraham Lincoln declared a national emergency at the beginning of the civil war, but the supreme court blocked that declaration. 

What if it is found that a foreign terrorist organization definitely has multiple dirty bombs and possibly an actual nuclear weapon that's been smuggled into the US? What if it is known that a conglomerate domestic fundamentalist terrorist organization is, and already has begun to carry out nation wide mass shootings at large gatherings, on crowded highways and schools, and large scale gas attacks? What if Congress or the supreme court stands in the way of allowing a president to enforce a national curfew, or certain states refuse to allow federal troops in to their state? What if there are members of all the branches of government who do sympathize with these potential terrorists? 

Do you believe that during a disaster situation, there is, or should be a threshold where all civil liberties espoused in the constitution should be void and all governing decisions be given to a single government entity?