Syrian Citizens Rebellion

Some may argue that when the population resorts to force to deal with the inability of its own government, it is a rebellion and civil resentment (or war) rather than terrorism. The population of Syria, these proponents would argue, are not terrorists, but rather people who were fed up with an oppressive regime. Moreover, Syria was not a failed state at the start of the current war and only become one as a result of influx of external terrorists. So how would we square these inconsistencies with the argument that violence from within from the population is the cause of terrorism?