The exact nature of what is going on inside Syria is tough to determine. The United States, Britain, France and Israel have focused on the question of whether forces loyal to Syrian President Bashar Assad have used chemical weapons. To answer that question and understand its implications, some myths need to be dispelled.

1. Witness reports can establish the use of chemical weapons.

Because Syria has blocked United Nations inspectors from entering the country, much of the "evidence" in play is from witness reports. The most detailed of those came this past week from France's Le Monde newspaper: "No odor, no smoke, not even a whistle to indicate the release of a toxic gas. And then the symptoms appear. The men cough violently. Their eyes burn, their pupils shrink, their vision blurs. Soon they experience difficulty breathing, sometimes in the extreme."