From historian Andrew Roberts, in The Wall Street Journal, comes this:

There is a long and honorable history of the civilized world treating those dictators who use poison gas as qualitatively different from the normal ruck of tyrants whose careers have so stained the 20th and 21st centuries.

President Obama, who talks endlessly of the importance of civilized values, must now uphold this one.

What he said.  RTWT.