The best thing for you to do is to read up on towing and tow vehicles so you can understand all the variables that go into this question. Start here
ClickyFor instance "For a 7200lb trailer a 3/4 is an imperative under any circumstances." My 1/2 ton will handle a fully loaded 8500 lbs fifth wheel without a problem, and still have room for 625 lbs of passengers and gear; all within all its manufacturer's ratings. Lots 1/2 tons could not. So "Imperative under any circumstances" is flat out wrong. Its all in the details, hence, the need to read the clicky.