For the Western world, the choice is of extreme complexity, posing an awesome mess of interests and factors both legal and moral. Probably, the line was drawn at chemical weapons with the hope that Bashār al-Asad would avoid using such a device, mainly harming civilians; secondly, it was to justify why no earlier attempts were made to intervene in the all too bloody civil war.
Now the use of CW and the more than thousand deaths are a fact. Public information available, so far, points to the chemical attack as carried out by forces commanded by Bashār al-Asad. At the same time, it cannot be completely ruled out that the attack was an attempt by some rebel grouping to provoke the West into war. Still, the latter version is hard indeed to believe, considering the circumstances.
The question of whether, when exactly and how to attack the Syrian governmental forces for using CW on their own citizens probably poses the hardest issues the US president Barack Obama has ever faced in his time in office. Now, he has directed decision-making to Congress, with the vote supposed to happen next Monday. Considering the reactions by USA’s allies and the domestic differences, one may understand the desire for support as broad as possible. During the week to come, the UN report by experts sent to Syria ought to be completed as well, hopefully with added clarity for global public at large.