The White House has posted cringe again

And I'm pretty sure (without looking it up) that his very first villain was a slumlord.

EDIT: I was mistaken, though I'm pretty sure he threatens a slumlord in an early issue of Action Comics. Here's the actual summary:

The next twelve pages showed Superman attempting to save an innocent woman about to be executed while delivering the real murderess, bound and gagged, and leaving her on the lawn of the state Governor's mansion after breaking through the door into his house with a signed confession; coming to the aid of a woman being beaten up by her husband, who faints when his knife shatters on Superman's skin; rescuing Lois Lane (who also debuts in this issue) from a gangster who abducted her after she rebuffed him at a nightclub, which leads to the cover scene with the car; and going to Washington, D.C. to investigate a Senator who he suspects is corrupt, prompting a confession by leaping around high buildings with the terrified man, which leads into the next issue. All the while, Clark tries to keep Superman out of the papers.