Then you do not understand America.

Why constitution grants citizens to have gun?

"Rightful liberty is unobstructed action, according to our will, within limits drawn around us by the equal rights of others."

-- Thomas Jefferson

"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

"The very atmosphere of firearms anywhere and everywhere restrains evil interference - they deserve a place of honor with all that's good"

-- George Washington

"The best we can hope for concerning the people at large is that they be properly armed."

-- Alexander Hamilton, The Federalist Papers at 184-188

"They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."

-- Benjamin Franklin, Historical Review of Pennsylvania, 1759.