1. US and allies blamed for horrific civilian deaths. Gory pictures of children will be shown. I would not put it past COL Q to inflict these casualties himself if there are no 'real' ones he can exploit.
2. Anti-US fervor to be stoked any place where they need an excuse.
3. Given that Libya does not have a strong military class nor a middle class, there is a great deal of uncertainty as to how the country could be reconstituted under a new ruling government or how it might be partitioned into a new rebel led territory and the balance led by COL Q. Should this happen, the Western powers would have to remain in place until COL Q goes.
4. Any new government might be fundamentalist in nature and present a whole new set of issues.
Just my take off the top.