Defense Secretary Esper has prepped resignation letter, say officials

Meh, if he's standing for what he believes is right I can respect it. As for the base name change, personally I won't lose any sleep over it either way, but I can see why some are pushing for the name change

What does he know that has him wanting to resign?

Well - either way he was going to be gone so...I guess ending it on his terms is better.