The government of Syrian President Bashar al-Assad had better take note. Hillary Clinton drew a line in the sand on Monday, threatening to intervene in the country’s 20-month-old civil war if his troops use chemical weapons. “Suffice to say we are certainly planning to take action” if the threat looks imminent, the secretary of state said. Syrian officials countered that they were not planning to use any weapons of mass destruction. The United Nations announced that it is withdrawing all nonessential staff from the country because the security situation continues to devolve.