WASHINGTON — To supporters of the Iran nuclear deal, it's no surprise that President Donald Trump is now facing a potential war with Iran.

Long before Trump was elected, advocates of the nuclear agreement — including then-President Barack Obama, French President Emmanuel Macron and others — had argued that abandoning the accord carried grave risks that could lead to an armed conflict.

"So let's not mince words. The choice we face is ultimately between diplomacy or some form of war — maybe not tomorrow, maybe not three months from now, but soon," Obama said in a speech in 2015 defending the deal before a congressional vote.

Trump as a candidate vowed to dump what he called "the worst deal ever" and he made good on his promise in 2018. A year later, Trump is openly discussing the pros and cons of bombing Iran.

On Friday, the president said in a tweet that he had ordered and then called off military strikes against Iran after Tehran shot down a U.S. surveillance drone over the Strait of Hormuz.

In his 2015 speech, Obama said that without an agreement limiting Iran's nuclear program in return for sanctions relief, any U.S. administration would be left with only one option to prevent Iran from getting a nuclear weapon — "another war in the Middle East."

Obama said that Iran — unrestrained by the nuclear accord — would soon be on the threshold of developing an atomic bomb. "Without this deal, Iran will be in a position — however tough our rhetoric may be — to steadily advance its capabilities. Its breakout time, which is already fairly small, could shrink to near zero."

"Does anyone really doubt that the same voices now raised against this deal will be demanding that whoever is president bomb those nuclear facilities?" Obama said.

At the time, Republican opponents of the 2015 nuclear agreement, known as the JCPOA, dismissed the idea that the alternative to the deal was waging war on Iran.

Macron and other European leaders repeatedly urged Trump not to abandon the agreement, and voiced concern that the collapse of the accord carried dangers for an already volatile region.