Obama attempted to close gitmo. Then states started passing laws to ban the housing of those detainees and Republicans in Congress threw a giant hissy fit, including a straight up ban on housing those prisoners anywhere.

“May 19, 2010: The House Armed Services Committee rejects the Obama administration’s plan to bring Guantánamo detainees into domestic prisons by approving legislation that prohibits detention centers inside the U.S.”

Full timeline here with additional links: https://www.theatlantic.com/international/archive/2013/01/obama-closing-guantanamo-timeline/318980/

I think the only campaign promise Obama straight up broke was regarding horse meat. It was banned. He said he’d keep it banned. Then suddenly he signed the law allowing it, so now your beef products probably also have horse meat in them and there’s no requirement for companies to disclose that to you. https://www.washingtontimes.com/news/2011/nov/30/obama-congress-restore-us-horse-slaughter-industry/