During the presidential campaign he promised he wouldn't intervene in foreign conflicts but after seeing the horrific images from a "barbaric" sarin nerve gas attack in Syria , Donald Trump ordered a missile strike on the country.
He had earlier called the use of chemical weapons which killed around 100 people in the Idlib Province, an "egregious crime" and a disgrace to humanity".
But when asked whether Syrian President Bashar al-Assad should leave power, he gave the vague answer that "something should happen".
Within hours of that statement, the US fired around 60 Tomahawk missiles onto the facility near the city of Homs where the chemical attack was launched from.
It appears to have been a video of the chemical attack that prompted Mr Trump to take action.
The horrifying footage showed rescue workers trying to save those affected by the nerve agent. Several children could be seen struggling to breath and dying on camera.
Images of a father holding his twin toddlers who died in the attack have also been widely circulated as well.
This was not the first attack during the Trump presidency nor the worst, but it appears to have been the one to change his mind.
The US President expressed his disgust with the use of chemical weapons during his joint press conference with the visiting King Abdullah of Jordan, an important US ally in the region.
However he did not say air strikes were on the table. Instead, he blamed the Obama administration for "the mess" he inherited.
Mr Obama had issued a warning to Syria in 2013, saying chemical attacks were a "redline" due to their severity. However, once the "redline" was crossed Mr Obama was unable to take action because he did not receive approval from Congress at the time.
Mr Trump did not seek approval from his fellow politicians.
It was actually US Ambassador to the United Nations who may have signalled the beginning of a quick turnaround on US policy on Syria.
Holding up images of the child victims, in an address to the UN Security Council, Nikki Hayley blamed Russia for their adversary role in supporting Mr Assad in Syria
The council decided not to vote on a resolution regarding Syria just hours before the US missile attack.
Secretary of State Rex Tillerson also said shortly to the chemical attack that the fate of Mr Assad was in the hands of the Syrian people.
Afterwards he said the US was considering an “appropriate response” to the use of a nerve agent.
Mr Trump also got support from an unlikely source - his former rival for the US presidency, Hillary Clinton.
Speaking at the Women in The World Summit the former Secretary of State said she believed the US "should take out [Mr Assad's] air fields and prevent him from being able to use them to bomb innocent people and drop sarin gas on them."
After the missile launch Mr Trump, who is meeting with Chinese President Xi Jinping at Florida golf club Mar-a-Lago, made note of the "beautiful babies" who died in the chemical attack and that "no child of God should ever suffer" in that manner.
He cited UN resolutions and threats of action as failures and lamented the continuing refugee crisis. Mr Trump placed Syria on the list of countries whose citizens are banned from entering the US.
He then called "on all civilised nations to end the...bloodshed in Syria."
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