Experience shows that, on such situations, firearms are good for attacking but terrible for defending. It all boils down to the element of surprise: the thief knows he's going to attack you, but you are not aware of it, giving you no adequate time to respond.
There are some cases of success, usually extensively mentioned by supporters, but the reaction is often conducted by a third party who arrived at the situation after the first approach, or when the criminal is distracted, which makes all the difference, since it transfers the element of surprise to the victim.
I would be more inclined to agree with lesser firearm restrictions if the government were talking more about training, prevention and awareness, with guns being used only as a last resort in a broader defense strategy. But, we know that's not what's happening. They just try to make us believe we should react if we will.