For example, we know that bad guys use guns to commit crimes, yet we're very very reluctant to ban guns. Bad guys use cars, but we don't require cars to come with remote kill switches.
Bad guys use encryption. Shall we therefore ban it? Or destroy its effectiveness? Do any good guys use encryption? And should we take those uses in to consideration as we think about public policy?
The President of the U.S. uses an iPad. Millions of federal employees, including FBI agents, use iPhones. Let's think about the implications of punching a hole in the security of those devices.
It's very easy to make decisions when one ignores the broader context and consequences. That doesn't mean it's the right way to make decisions.