The former administration's policies "empowered Russia and Iran, produced ISIS, strengthened al-Qaeda and created the refugee crisis which became a strategic threat to Europe," according to one analyst from the BBC. These were astonishingly reinforced by the Obama nuclear deal, which not only guaranteed American nonaggression but also provided a source of money to pursue the Islamic Republic's ambitions.
Worth noting, things went to hell in a hand-basket on this.
Now, Iran under the Shah was actually friends with Israel, now the two countries are dire enemies.
That was a disaster, Camp David with Carter I believe, that might have actually worked. It is worth noting all of this.