A. Mitchell Palmer, a.k.a. The Fighting Quaker, was a politician and Attorney General from Pennsylvania, he's sort of a mixed bag of crazy nationalist rhetoric and well-intentioned but ultimately dangerous beliefs. Both a progressive and an anti-progressive at different points in his life, he opposed big business and support labor at one point but also attempted to disrupt many strikes. He envisioned the first "Red Scare" and once encouraged the country to prepare for a radical overthrow that never occurred. Mostly, he was a supporter of the idea that a country could do whatever it wanted to in wartime including seize the assets of foreigners residing legally in the U.S. via the Alien Property Custodian office. It's clear he probably got along well with Henry Ford and Thomas Edison, who attempted to build an electric car when they weren't investigating commies or borrowing ideas. Especially considering it was the Alien Property Custodian office that seized Nikola Tesla's stuff when he died. Spiegel1 thanks that Tesla feller had some good ideas.
Thanks to Palmer we have the ACLU. Not because he founded it, but because he was so awful they formed to stop him.