A Syrian soldier wearing protective gear for fighting in chemical and biological battlefield conditions. Photo: Wikipedia Commons

U.S. President Barack Obama warned of "enormous consequences" if the Syrian government or other actors in the country began to move large quantities of the regime's chemical and biological weapons, or endeavored to use them.

The President noted that in the volatile conditions of Syria, oversight of the location and status of the weapons stockpiled by the al-Assad regime was difficult. Obama noted that the U.S. was "not absolutely confident [on the status of Syria's chemical weapons], but monitoring the situation closely."

"We cannot have a situation in which chemical or biological weapons are falling into the hands of the wrong people," said Obama, referring to the potential for Syria's unconventional arms -- believed by experts to be the largest stockpile in the Middle East -- to be transferred to terrorist or extremist groups.

In late 2011, U.S. defense analysts had already begun to warn that the downward spiral of violence and instability in Syria would begin to jeopardize the security and protection of the regime's chemical and biological weapons. U.S. intelligence estimates are confident that Syria has weaponized stockpiles of the nerve agent sarin, and may also hold the deadly VX, tabun, and mustard gases.

Slightly more than a month ago on July 13, the Pentagon remarked that it still believed "the Syrian regime has control of its chemical weapons stockpiles." As fighting expanded in the capital Damascus, in the largest city and commercial hub Aleppo, and along the Turkish border, and as the regime began to lose control of northeastern parts of the country to Kurdish groups, that control began to look far less certain.

Nonproliferation experts such as Leonard Spector of the Monterey Institute of International Studies are concerned about whether there are contingency plans for securing the weapons if they ended up in regions outside the control of president Bashar al-Assad's regime. Rebel forces may lack the knowledge or manpower to secure the sites if they are deserted by government troops. Also in question is how the stockpiles would be dealt with in the aftermath of the Syrian conflict, whenever that is.

Obama did not specify what he meant by his "changing calculus" -- some degree of intervention from the West remains possible among multiple fronts. Those include the imposition of a no-fly zone; bombing strikes on the Syrian military; channeling arms or training to the Free Syria Army; and the insertion of special operations forces or even potentially of thousands of troops on the ground.

Estimates of the size and dispersion of Syria's chemical weapons stockpile however, vary greatly, anywhere from half a dozen to two dozen sites around the country. That level of uncertainly would require more personnel to hunt and secure sites. Air strikes also create the risk of exposing agents to the open. Syrian forces could also begin moving stockpiles more actively inside the country, or even taking them outside of it. All those factors would increase the necessity of a major intervention requiring the deployment of larger groups of ground forces.

In July, small numbers of chemical weapons were rumored to have been moved outside of storage by elite Assad loyalist forces charged with their protection. Syrian experts believed at the time that the regime was seeking to move them into more secure locations, rather than to actually use them.

The Syrian foreign ministry noted back on July 23 that it would never use unconventional weapons on its own citizens and people, but would not exclude their use against foreign aggressors.

In an impromptu press conference on Monday, President Obama offered a stark assessment of the situation in the country, located at the historic heart of the Arab world and the Middle East.

A "soft landing seems pretty distant," said Obama. The U.S. government has already promised $82 million in humanitarian assistance to refugees that have fled from Syria into neighboring countries. The president said that figure is likely to increase as the situation in the country continues along its present self-destructive course.

Activists and Syrian opposition groups estimate that more than 20,000 have perished in the country's anti-government uprising, now turned into civil war, since March 2011.