international driving permit

No. You can drive with only your state-issued drivers license.

But it's not a bad idea to have one. If you do get stopped for a violation, it makes it easier for the police to have the right information from your real license. (Which is your birthdate and which is the expiration date?) And you want the police to be happy.

Unlike here, the police officer can make a judgment call to collect the fine from you on the spot. Knowing that, some travelers choose to pay the $15 to get the IDP, which translates your license expiration and other data into French (among other languages) so the officer isn't forced to translate your US license into French on the spot, which might irritate him. Obviously, we don't know if that strategy works, but some travelers make that choice.

If you have a AAA office nearby, which it seems you would in Tampa, I think it would be worth the $15 to get one. They can take your picture, put together the license, and you walk out the door with it. It took me about 15 minutes.