The current situation in Syria can't be charaterized as "obvious and clear", although the regime of Bashar al-Assad posses chemical weapons, no strong evidence provided that during 21 aug. massacare they are the ONLY responsable for killings. Also the reports showing that partially the rebels belongs to Al-Qaeda terrorist organization.
According to international law it's stritctly prohibited to use military force without against independent country without sanctions from the UN SC.
The UN SC has released multiple sanctions on multiple countries and not much has come out of them. The US has the ability to clear the situation. They can use airstrikes to destroy chemical plants or commandos to destroy the supplies. The UN SC takes to long to act and Russia, who is on the counsel, is said to be an "ally" of Syria in that they supply them. The threat of chemical proliferation is high and the faster the problem can be resolved the better.
The argument doesn't cost a thing. All the information and propaganda which goes through mainstream mass media should not be considered as a truth of last instance. Its stated in the INTERNATIONAL LAW, NONE CAN INVADE Sovereign country. US should be accused multiple times for breaking INTERNATIONAL LAW.
The latest UN investigation shows that is its not clear, who and how many times used chemical weapons, as Mr John Kerry, that he have evidence. SHOW the WORLD evidence, Iraq scenarion repeat.