US will now come under pressure to escalate in Syria
US President Donald Trump's decision to intervene in Syria, sweeping aside the efforts of his predecessor to keep the US out of the conflict, will reverberate far wider than issues of chemical weapons alone.
The strikes sent a powerful message that use of these deadly weapons won't be tolerated, but they risk fuelling a new escalatory cycle in the civil war and pulling the US, slowly but surely, deeper into the fighting.
At first glance these missile strikes appear largely symbolic. Not only was Russia - and therefore Bashar al-Assad - warned, but the Tomahawk cruise missiles took out a number of Syrian fighter jets without destroying the airport's runways. New Syrian combat missions were being flown from the same base the very next day.
Mr Trump reinforced this interpretation by emphasising that the key aim - beyond the self-evident desire to show strength at home - was to ensure that Assad refrained from further use of chemical weapons. However, the US is likely to have unleashed far more than it anticipated, particularly given the lack of any meaningful political strategy to follow the military attacks.
Once the US wades in, it rarely succeeds in containing its own ambitions, let alone those of its allies. In the context of a brutal six-year conflict driven by zero-sum ambitions on all sides, this is a heady cocktail.
On the ground, and across the region, the warring parties will be betting on renewed US intervention. The air strikes thus risk re-energising all parties for intensified war at a moment when some were hoping for a denouement given widening fatigue and an overdue acceptance that Assad will not be militarily defeated.
The rebels, long intent on drawing the US into the conflict on their side, already see these initial strikes as the thin end of the wedge. They, and their regional allies, Saudi Arabia, Turkey and Qatar, will do all they can to draw Washington in deeper.
Assad and his key backers, Iran and Russia, will in turn double down on their own positions. They will certainly not fold in response to the US show of force, with Assad's position on the ground stronger than ever. The regime in Damascus remains committed to total military victory.
Much will now depend on whether or not Mr Trump is able to hold back and transmit a clear message that the US will take no further military action.
But he will face intense pressure to escalate US involvement, having tied his own credibility to the outcome. Despite efforts by UK foreign secretary Boris Johnson to tie the G7 to a co-ordinated response, the odds are stacked against any new political process without the buy-in of Russia and Iran.
Mr Trump is increasingly defining himself in opposition to Barack Obama - this response to the use of chemical weapons being the clearest example - and he will struggle to resist escalating the United States' involvement as he seeks to differentiate himself from the perceived weakness of his predecessor in shaping an outcome in Syria.
Julien Barnes-Dacey is a senior policy fellow with the European Council on Foreign Relations