Fortunately, our founding fathers made provision for this sort of thing:
Quote: (The Congress shall have Power) To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions
Article 1, Section 8, Clause 15
And here, all the while, the gun nutters would have had you believe that the "militia" was designed to protect us from a tyrannical government. Speaker Pelosi, call forth the militia!