The union that represents Foreign Service Officers naturally does its best to be diplomatic, but the strain is evident in a standoff with United Airlines over a recently adopted pet transportation policy. The new policy, which follows United’s merger with Continental Airlines, requires most pets to be shipped as cargo, instead of permitting them to travel with their owners as baggage. The fur, at least, has been flying ever since. “Many of our members are greatly distressed by this development because of the sharply increased costs involved,” Susan Johnson, president of the American Foreign Service Association, wrote in a letter…