...OK. What about Hitler and guns? Let's take a look:
Hitler did not take away guns from Germans. He actually loosened the very strict gun laws of the Weimar Republic. He didn't rule Germany as a tyrant because Germans were unarmed; he stayed in power because most Germans at the time supported him.
Armed opposition is no more effective than unarmed opposition against tyrants in our time. Look at the list of tyrannies that have fallen to non-violent protests: the Soviet Union, East Germany and all the East Bloc dictatorships, the military regimes in Argentina, Chile and Brazil, Mubarak, Tunisia, the Shah of Iran, apartheid South Africa, Marcos in the Philippines, and many others. Now look at the record of armed opposition-Libya- Qaddafi only fell because of NATO intervention; Syria-50,000 dead and the outcome is still uncertain. Let the record speak.