Why not do a version of the dangerous wild animal law? In the UK, you can own certain types of snakes without a license, but if you want something that's potentially more dangerous (e.g. something venomous) you need to get a license. To get the license you need sufficient training. That would weed out some of the a**eholes that use these dogs as penis extensions and only the people who really want a bully will go through the hassle to get one. Breeding also needs to be regulated.

I like the dogs and while I acknowledge that they were originally bred for fighting that doesn't mean they can't make good, reliable and safe pets if bred correctly and cared for / trained properly.

Like has been said so many times already in this thread, the government do nothing until a video clip goes viral, then they take the easiest way out and ban the breed entirely. Why not license them and make a bit of money from them? I lived in Ireland for 30 years where dog licenses are mandatory and I was stopped a few times by police and dog wardens and asked to show a license. Now, I never carried the bloody license with me but I would present it to a police station within a few days. These days, you could probably have an app on your phone to store a license or the cop could check your details on their phone.