On April 4, a barbaric, inhuman, heartless chemical attack targeted Khan Shaykhun in rural Idlib Governorate in northwest Syria, claiming dozens of civilian lives including children. In response to the chemical attack, the Trump administration struck Shayrat Airfield near Homs with 58 Tomahawk missiles. Although the strike certainly represented a pivotal point in the conflict in Syria, I think it was also the emergence of the Trump Doctrine, which can be summed up in the following points: Independence of US decision-making from Moscow. The Trump administration wished to demonstrate to Americans and to the international community that its decisions are independent of Moscow and that US interest is always its priority. It is true that the strike was not discussed with Moscow, as was shown in the remarks of the US Secretary of State Rex Tillerson, who said: "There were no discussions or prior contacts, nor have there been any since the attack, with Moscow". Moreover, in a joint press conference with Lavrov, Tillerson said: "The current state of US-Russia relations is at a low point ... [neither country can afford] this kind of relationship". Through striking the Russian-backed Assad regime, Trump achieved his aim of showing that his decision-making is carried out independently of Moscow. At the same time he managed to dispel allegations concerning his relationship with Russia, which plagued him throughout the election campaign and even after he won the presidency. Contradicting Obama's diplomacy. Eight years of US retreat from international affairs during Obama's two terms allowed regional powers to fill the vacuum. Russia, for instance, significantly benefitted during this period by strengthening its presence in the region, especially in Syria. Therefore, the current US administration aims to restore American leadership as a superpower in international policy. Sanctity of red lines. The previous US administration talked at length about red lines, which were repeatedly crossed by the Syrian regime without any punishment. The consequent disrespect for Syrian blood by the Syrian regime was manifested in the dozens of daily massacres carried out by the regime's aircraft against innocent civilians. Hence, unlike the previous administration, Trump appeared more decisive by punishing the Syrian regime for its failure to comply with chemical weapons agreements. The timeliness of the decision-making, not waiting for investigations, and the firing of 58 Tomahawk missiles were a clear message to Assad that crossing red lines will not be tolerated. Putting pressure on Iran. The previous US administration went to great lengths with Iran in order to make the nuclear deal a success. As a result, Iran began to interfere in regional affairs. Had Iran not backed the Assad regime at all costs, Assad would not have been able to hold on this long. Thus, the missile strike sent a clear message to Iran that US policy has changed, and that there has been a shift in dealing with Iranian rebellion in order to put an end to Iranian expansion by curbing its militia's support for Assad in Syria. The most important thing is that this involvement in the region must be followed by a comprehensive American strategy to deal with regional issues, at the top of which is the Syrian conflict. Although it is still too early to predict, the fallout from the missile strike will undoubtedly have an impact at regional and international levels. Dr. Ibrahim Al-Othaimin is a Middle East affairs specialist and security analyst based in Riyadh. He can be contacted at [email protected]. Follow him on Twitter @Alothaimin