The second amendment provides for American citizens to protect themselves from the government in a possible time of tyranny. Gun laws have shown to only limit law abiding citizens from protecting themselves in times of need. If the Federal government demands restrictions on the people, then they must set the example and belief it works, by disarming the government of the same weapons.
If Americans have no need for "assault" weapons to defend themselves, there is no need for the Federal government to have them either, especially if this form of gun control works.
Leadership is shown by setting the example, not telling others how to be.