Alternet has a good interview with Naomi Wolf that should be read in full, but here's the quote that speaks to discussion we've been having here about defining tyranny.
...But what's so ironic about that is that the Founding Fathers drafted the Bill of Rights in fear. They knew that you had to have checks and balances, because it's human nature to abuse power, no matter who you are. They knew the damage that the army could do breaking into your home. ... they knew that democracy is fragile, and the default is tyranny. They knew that. And that's why they created the system of checks and balances.
That system has been nearly destroyed during the six years of one party rule we've had in this administration. It's in bad need of a recalibration since Bush and his lackeys continue to thumb their nose at the accountability it mandates. A good start would be for our legislative branch to actually use its penalty provisions to compel compliance, instead of just threatening to do so. [via]