Should semi-automatics be banned because they make revolvers and pistols useless?

Here’s a question for you and one as to which I’m too ignorant to have an answer.  In response to my last newsletter regarding fallacies driving the gun control crowd (and you can sign up for newsletters here), I got the following email:

The average citizen only carries a handgun. They have now been rendered useless despite our right to carry as no handgun can go up against an assault weapon firing 100 rounds in seconds. The NRA’s insistence on arming criminals with assault weapons in the name of money has ruined any chances of my handgun being effective. The ban on assault weapons needs to be put back in place in spite of the fact that gun manufacturers will lose money. Make my handgun effective again! Eliminate Assault Weapons!!!!!

My instinct is that there’s a problem with the above logic, but it’s eluding me.  Or maybe the person is absolutely right, and I just don’t want to admit it.

As politely as possible, please address the truth or falsity of the above statement.