They're talking about personal courage/foolhardiness
Then Jackson ought to be #1. Even as a kid, he made people hate him - during the War for Independence, he ticked off a Brit cavalryman who slashed him with a saber (IIRC). He ran around fighting British and Indians in the South. I seem to recall that he hung two British folks in Florida (which was a big faux pas at the time). He ran off the Cherokee, threatened to invade South Carolina, fought duels... TR appears tame by comparison.