Isn't it just Trump that doesn't honor deals?

What did Bush / Obama / Biden do?

Going all the way back to the hostage crisis, the US never really held up their end of the deal. We were also quietly making inroads with the revolutionary government of Iran and then secretly backed Saddam Hussein in the Iran-Iraq war in 1980.

But the elephant in the room is Trump and the JCPOA. We just backed out and gave them nothing in return for them holding up their side of the bargain. Furthermore, we made such an embarrassment out of the other signatories that such a deal amongst western powers will never happen again either.