Also what abill_uk said, this will also help, i still recommend 2 component glue if you want to be totally rock solid, JUST be careful not to get it in the USB port it self, then you will never get a USB in there anymore.

Even if it is soldered down, you can still rip it off by ripping the copper lanes off or breaking them, but of course if you do this then you can never claim to be gentle with you USB port , because this will seriously take some force to do.

But to make a stronger USB just solder it down like abill_uk said, only the big sides of course, i will just do this on the new one i just got and post pictures, in the next hours that is.