Obama could also cite the actions of two politically incorrect precedents, and presidents James K. Polk in Mexico and Richard M. Nixon in Cambodia. The former would make the Democrats no friends among Hispanic voters, who have increasingly become an important part of the party’s political calculus. The latter is poison for a liberal Democrat who turned 13 only five days before Nixon resigned. A safer example: Woodrow Wilson in Mexico in 1913, though Wilson is toxic among the sippers of political tea.
Presidents with high approval ratings can sometimes split the difference. George H.W. Bush told -- that word is essential here -- congressional leaders about the Panama action after a Christmas party in 1989 and only hours before the operation began. Then again, before moving against Iraq in 1991, Bush sought and won congressional approval.
Is there, as Obama and Secretary of Defense Chuck Hagel suggested, a modern-day domino theory at work, or could there be the phenomenon of Appeasement Redux?
Hagel is a veteran of the Vietnam War, which was prosecuted in large measure out of fear that if Vietnam fell, then so might Laos, and then South Korea and then perhaps Japan as well.
There certainly is regional tumult in the area of the globe once known as the Levant. But just as that term has fallen out of favor -- it’s mainly used today by archaeologists -- so may have the metaphor of the domino, which in any case belongs more to the 17th century than to the 21st. Nearly two years after the beginning of the Arab Spring, we now know there are many Arab Springs; the one in Egypt was different from the one in Libya and elsewhere.
The war in Vietnam also was prosecuted on the basis of the lessons of Munich, which postulated that if aggression were unanswered in one place (Czechoslovakia) then there would be aggression again in other places (Poland). That certainly was true in 1938, but it may or may not be true three-quarters of a century later.