there are reports that kadhafi is already using the military to attack opposition actions.
well, the interior security forces as he has apparently been afraid of a military coup since he came to power via a military coup in 1969 so has worked to keep the military weak...libya is controlled by the interior security forces that overlap with effectively private militias----you know, the kind of feudal arrangement that would result in a lot of place as the logical outcome of taking conservative paranoia about the state seriously
there are reports of military jets being used.
there are reports that there are naval vessels in position off tripoli that may be used to bombard the city.
so no, there's no reason to worry too much about what might happen.
the international community has a great track record of not knowing what to do when massacres present themselves:
Rwanda: Why the international community looked away | World | Deutsche Welle | 07.04.2009
much better to sit around and watch people get massacred and complain about how o so terrible it all is.