U.S. Ambassador to NATO Ivo H. Daalder drew the lessons prom the Libyan precedent before the Atlantic Council, on 7 November 2011.
In the discussion that followed, the first question centered on a possible intervention in Syria. The ambassador then laid down three conditions for achieving this:

a compelling situation (in Libya, international public opinion was made to believe that Gaddafi was about to raze Benghazi);

regional support (the Arab League);

an international mandate (for now, the BRICS countries - including Russia and China which hold veto power at the Security Council - are opposed to it).
Inversely, from this reply it is possible to infer the strategy of the US:

pin on Bashar Assad the intention of razing Homs;

enlist support from the GCC and the Arab League;

put pressure on Russia and China.
River to Sea
Uprooted Palestinian