Why would congress need protection from their constituents?

Maybe congress should listen to their constituents before requesting protection from their constituents!

However, threats and violence are nothing new for the American populace when faced with a government that does not listen and respond to the governed. Although I do not necessary agree with violence at this point within the country against our elected representatives; the government should review the document that formed our country and the right and duty, we as citizens of this great experiment have to provide for our future security.

Anyone remember reading this passage in US Civics class?

That whenever any form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.

Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience hath shewn that mankind are more disposed to suffer, while evils are sufferable than to right themselves by abolishing the forms to which they are accustomed.

But when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.

And hence the 2nd Amendment...
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.

And why the second amendment?

"No free man shall ever be debarred the use of arms. The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government" -- Thomas Jefferson, 1 Thomas Jefferson Papers, 334