The larger point is, if "secure" devices are illegal in the US, who is going to make them and what are they going to cost? The FBI/CIA/NSA/DOJ/etc all use mobile phones, tablets, and computers. Will all of these government agencies be using special devices built only for them, perhaps by another government agency?

The FBI having the ability to break in to NSA or DOJ machines is definitely not ok and I'm not sure anyone is going to say otherwise besides the FBI. Hell, we can't even trust the FBI agents with a few bitcoins.