The A-10 is the Thunderbolt II, named for the P-47 Thunderbolt. Both were designed and built by Republic.
@PeteS in CA I had forgotten all about the WW-2 workhorse.
Besides the A-10,as a grunt,I was kinda fond of the A1E Sky Raider.,too. If you are a grunt,there is a LOT to be said in praise of the old prop planes that could fly low and slow,and really deliver the damn-damn where you needed it.
Plus,I liked the leather WW-2 helmets the pilots wore,and the fact that after a run,they would sometimes come back and fly over us with the canopy pushed back and do a barrel roll while smiling and waving at us.
Fast movers were ok,but when you were in it deep,what you wanted was slow and accurate cannon and bomb runs.