BoycottUnitedStates

It's a difficult process, and very, very few make it through. It requires a 2/3 vote of the House and Senate, and then 3/4 of the states have to vote for it. Almost 12,000 amendments have been proposed, but only 27 have been ratified.

The 27th is weird one, having been first proposed in 1789, but not finally ratified by the states until 1992. Usually, there is a 7 year limit on the States' votes. The previous one, the 26th, was in 1971. The biggest failure between those two was probably the Equal Rights Amendment, which faced a fierce battle by Conservatives, who don't feel it's necessary to codify equal rights for women.

There are a number of unratified amendments out there, most of which have been dormant since the 19th century, and will probably never be finished.

It is almost impossible to get an amendment proposed and ratified today. The 2/3 approval by Congress, and then 3/4 of the states, are nearly impossible hurdles in the current political environment.