The use of chemical weapons anywhere in the world is an affront to human dignity and a threat to the security of people everywhere. We have a duty to preserve a world free from the fear of chemical weapons for our children. -- Barack Obama, (14 Sept. 2103.)
Uhuh... Now, Barack Obama wasn't born when the prize-wining photograph made the world news but we are not interested in Obama as a private golfer. As president of the United States he is the official voice of the country he represents; and the country he represents is the very stuff of loathsome hypocricy.
Nor is it relevant that other countries may also commit atrocities. At least they do so without pretending (with "humble exceptionalism") that they are Jesus Christ or Eternal Victims.
The United States argues that napalm and white phosphorus are not "asphixiating gasses" and are therfore perfectly legal. However they are chemicals and are perfectly horrible.