Every time the discussion of gun control comes up, invariably, the argument comes up that weapons like the AR-15 are needed so that we can overthrow the government if needed. On his blog, Badtux summed up this nonsense in his usual style (have a read).
The 4th Infantry Division has M1 tanks, Stryker infantry fighting vehicles, machine guns, grenade launchers, helicopter gunships, the works. If you concentrate, they’ll demolish you. If you don’t concentrate but instead scatter all over, you’ll be taken out in detail. Remember: the most important advantage the government has is INTELLIGENCE. We live in a ubiquitous surveillance state where your every movement is tracked by cameras reading your license plates and by the geopositioning information from your cell phone.
Another popular talking point is that the first action of a tyrannical government is to disarm its citizens. Think about this argument for a bit. Unless you can easily buy or build your own Sherman tank, Apache missile, cluster bombs, fighter jet, or an unmanned drone, your militia (if you want to call it that) simply does not have the fire power to give a modern military any challenge.
In other words, WE ARE ALREADY DISARMED. The only reason we are allowed what we are allowed is because the second amendment forces the government to at least let us have something. In short, the government is not afraid of kids with shiny black toys shooting cans of Tannerite.