The agreement of warring parties Russia, Iran and Turkey on so-called "deescalation zones" in Syria that are meant to be free of fighting came as a surprise to many observers. But upon closer inspection, it's clear to see that this step is the result of a changed constellation of power after the Trump administration decided to engage more strongly in the conflict than before.

To recount: On April 4, 2017, dozens of civilians - among them many children - were killed in an suspected chemical attack on the town of Khan Sheikhoun in northwestern Syria. US President Donald Trump made it clear that he blamed the government of Syrian President Bashar al-Assad for the attack. As a punitive reaction, he ordered airstrikes on Syrian government troops.

US attack was a clear message to Russia

This intervention may have added extra strain to bilateral relations between the US and Russia, but at the same time, it sent a clear message to Moscow: Since the surprise "Tomahawk warning," Putin can no longer do whatever he wants in Syria. And Trump's unpredictability may well have alarmed the more calculating Russian leader.

The Russian-Iranian-Turkish agreement no doubt brings some movement into the gridlocked positions in Syria. For the first time, almost all the parties in the conflict, as well as the relevant intervention powers, support an agreement to suppress the violence. The deescalation zones have also been discussed with 27 rebel groups.

More than anything, the agreed safe zones are a chance for suffering civilians to catch their breath and receive much-needed assistance. That's even though the zones are explicitly not the humanitarian safe zones that observers and human rights activists have been demanding for years.

Since the agreement came into effect last Saturday, the fighting between the rebels and Assad's troops has subsided somewhat. This is grounds for careful optimism, but it is in no way a turning point in this brutally fought civil war.

In this agreement, the devil is in the details. Certain "terrorist groups" such as the so-called "Islamic State" and other militias linked to al Qaeda are exempt from the ceasefire. But the fact that Russia, Iran and the Assad regime are allowed to define which organizations are "terrorist groups" is problematic. For the Assad regime, all opposition forces are terrorists.

Lack of international monitoring

The fact that there are no plans for international monitoring of the safe zones by the United Nations is also feeding skepticism about the long-term success of the plan. Additionally, Russia has been granted the privilege of being allowed to carry out airstrikes in the safe zones "when necessary."

The Trump administration has so far ignored the new agreement. Russia wants to close the safe zones to the US-led anti-terror coalition. But that's hardly likely to impress Washington. It would be far more important if US decision makers would formulate a coherent strategy for Syria to serve as a basis for negotiations with Russia. Then we'd know whether Moscow's concessions are purely motivated by tactics, or whether they represent a true change in course.

As things now stand, we can assume that without a Russian-US agreement taking into account the other regional powers in this conflict, the deescalation zone deal will not hold. And that's why the war in Syria is likely to continue with unmitigated hardship.