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Analysts say President Obama - reluctant to become entangled in the complex conflict - will likely focus on hampering the Syrian government's ability to carry out another chemical weapons attack.
Administration officials have said this would focus not on storage sites but on symbolic Syrian military installations. In addition to significant cruise missile-launching ships just west of Syria, there are strategic bombers from as far as the continental U.S. that could penetrate air defenses and drop bunker-busting bombs.
The U.S., in conjunction with the U.K. and France, is not currently expected to attempt taking out the Syrian air force or enforce a no-fly zone over Syria. Such aims would likely require at least several weeks of preparation and more substantial military resources.
Al Jazeera and GlobalSecurity, Stratfor, and Syrian Network for Human Rights