While Republican candidates today win kudos for signing Grover Norquist’s anti-tax pledge, it is unlikely that Lincoln would sign on, since he, in effect, invented income tax. That is to say he was the first American president to sign federal income tax into law. And not only that, but it was a progressive income tax, with the wealthiest Americans paying a higher rate.
He made no distinctions between earned income and capital gains – money made was money earned – and Lincoln’s administration needed its cut to pull the nation back from the brink of collapse. Strike one against Honest Abe.