There is precedent that says the government may NOT prevent assembly of the people, if the purpose of the gathering is to petition the government for redress of grievances.
In Presser v. Illinois, some dude argued that the right to peaceably assemble, and the right to keep and bear arms both protected his right to conduct a parade with armed men, w/o a parade permit. The Presser court held that laws regarding parades do not interfere with the RKBA, and it also said:
The only clause in the constitution which, upon any pretense, could be said to have any relation whatever to [Presser's] right to associate with others as a military company, is found in the first amendment, which declares that 'congress shall make no laws ... abridging ... the right of the people peaceably to assemble and to petition the government for a redress of grievances.' This is a right which it was held in U. S. v. Cruikshank, above cited, was an attribute of national citizenship, and, as such, under the protection of, and guarantied by, the United States. But it was held in the same [Cruickshank] case that the right peaceably to assemble was not protected by the clause referred to, unless the purpose of the assembly was to petition the government for a redress of grievances.Washington, D.C. is under the exclusive jurisdiction of Congress, and Congress may not abridge the right of the people to assemble and to petition the government for a redress of grievances.
If the government revokes a permit for peaceable assembly to petition for redress of grievances, the government is acting in a clearly unconstitutional fashion.
From Cruikshank:
The right of the people peaceably to assemble for the purpose of petitioning Congress for a redress of grievances, or for any thing else connected with the powers or the duties of the national government, is an attribute of national citizenship, and, as such, under the protection of, and guaranteed by, the United States. The very idea of a government, republican in form, implies a right on the part of its citizens to meet peaceably for consultation in respect to public affairs and to petition for a redress of grievances.
Given the total lack of respect and regard that Congress has for the constitution, I would not be surprised at an action that denies permits to assemble. The government is cool with the idea of infringing the right to keep and bear arms, I presume it is cool with suppressing speech as well - see McCain-Feingold, for a law that does so.
Permits? We don' need no steenkin' permits! It's called freedom of assembly. In fact, we should take a page from the leftist/anarchist playbook and start flash mobbing from time to time.
Congressman/Senator So and So or a Michael Moore-on or Rosie O'Donuts is going to be at a particular location at a particular time; can we get hundreds there on a half hour notice?
Oh, that's right, it won't work; because we DO work!