There was a longer thread on this subject sometime back. The general consensus was it's a bad idea, however to each there own as I've happily ran with some sketchy loads in my truck before. My issue would be the 1/2 ton short bed truck. The bike alone puts you a near capacity and then your adding a trailer to it. Bike or trailer by themselves and you'd probably be alright but together I'd think you'll be asking for some type of mechanical/structural failure. You'll do what you need to make it work, however it may require some truck upgrades to do safely. Keep that in mind and with some thought an planning you should be okay.