They did in Egypt. Not saying it will go down like that here. We're too civil and we have the drop on them, unlike those other countries. And we have guns.
Not discounting them, but even without the guns, could you imagine tens of thousands of people massed in front of the Whitehouse? It would be a site to see and would be interesting to see what Barry & Co.'s response would be. The world would certainly be watching.
The problem would be finding that many people who are willing to leave their jobs and possibly family behind for an extended time that it would take for any real change to occur. And that is the difference between a place like Egypt and the US. The people who would be involved in something like this against the current administration are people with jobs/careers, mortgage payments and children they love. I don't believe that most of the protesters in Egypt had much in the way of real property and jobs to begin with.
I'm not saying it couldn't be or shouldn't be done, but the organization and logistics behind it would, in my opinion, carry a greater sacrifice and more then many people are willing or able to give.