Because a lot of people in America are afraid of tyranny from their government, not that they have experienced anything close to it or at risk from experiencing the tyranny they anticipate.
These people are paranoid to the point of averting their focus from the real threat and focus on what sensationalist media tells them.
Seems to protect some people, but in regards to the Constitution, it can be interpreted that all gun owners in the US must serve in the militia of their given state. Should that state not have a militia, they can either allow guns or confiscate them from civilians.
Also originally misread the title as a holster so that you could quickdraw out a bra at moment's notice.
