Obama's pursuit of the Iran deal led him to do nothing about Syria
...This is just more evidence of how really bad the Iran deal was and how it emboldened the Islamic religious bigot who rule Iran. While Obama should bear most of the responsibility for the mess he created, the liberals who supported this terrible deal should also shoulder part of the blame and they are in many cases not leaving office, yet.
What really tied Obama's hands was his own hands-off policy in Syria, part of an effort to avoid derailing nuclear talks with the Iranian regime. Obama's backing down from the red-line dealt a severe blow to American credibility and left a void that was quickly filled by Russia, which tried to pose as a peace broker in order to pursue its own political agendas.
Emboldened by Obama's backdown, Iran continued its military and financial support for the Assad regime with renewed fervor, pouring billions of dollars and thousands of troops into the war-torn country.
Obama also alluded in his remarks that nothing short of full involvement of United States troops would have changed the situation, which he compared to the failed 2003 Iraq invasion. But a dissent memo filed by 51 U.S. diplomats in June suggested limited military measures could keep Assad in check and place the international community in a stronger position to seal a diplomatic solution.
The proposition was rejected because, as Fred Hof, former State Department policy planner on Syria, said, the administration's main concern was that making Assad pay for mass murder would disenchant his Iranian patrons and threaten to scuttle the nuclear deal, the only red line Obama stayed true to during his tenure.
After the nuclear deal with Iran was forged, there was concern that Tehran would use the financial gains to further bolster Assad's crumbling regime. But no serious safeguards were put in place to ensure Iran would not spend the economic bonanza on its terrorist ventures.
The Obama administration's passivity in face of human slaughter prodded the Iranian regime to notch up its involvement in Syria and also draw Russia into the military mayhem to secure more gains.
After four years of siege, Aleppo fell not to Assad's military might, but to Iran's boots on the ground and Russia's warplanes. It will go down in history as one of the worst crimes against humanity to take place under the watchful eyes of the international community.