Why should Civil rights not be limited during a crisis?

I need some arguments for this. If you can please provide some exmaples that would support that argument.

Because imposing unConstitutional oppression upon even one person during a time of crisis nullifies any and all sacrifice that has been made in the past to protect those rights. Hundreds of thousands of your countrymen have died to protect your right to free speech, to keep and bear arms, to be protected from your government and others in your pursuit of happiness. To take any inalienable right away from you by force is an act of treason. If it is taken away by your government, then you have 100% right to wage war upon it, your government, for treason against the people.

The constitution allows for certain rights to be suspended in a crises, it's absolutely necessary in some situations.

The current situation of the War on Terror is different to the usual crises however - it's not as intense and all-consuming as WWII or the civil war and isn't likely to end soon. Because the protagonists are terrorists who fall outside the rules of war, the situation gets even more difficult.

This makes it difficult to hold POW's (legal and not) for the usual time - till the end of the hostilities. The supreme court has ruled as such.

That's one example.