The objective. In Afghanistan, the goal of toppling the Taliban was easily achieved, but damaging the al Qaeda network — much less getting bin Laden — took a long time. Further, nation-building has proved complicated, to say the least. In Iraq, regime change was effected, but there were no weapons of mass destruction, and whatever ties there were to al Qaeda arose only in the wake of the U.S. invasion. The establishment of democracy resulted in the victory of a political movement more aligned with Tehran than with Washington. In Libya, Muammar al-Qaddafi was defeated and killed, but al Qaeda now prospers there and radical Islamists struck a humiliating blow against the United States in Benghazi. Scores: Afghanistan, 6; Iraq, 4; Libya, 5.

The offensive. The intervention in Afghanistan began with a striking, swarming attack on Taliban and al Qaeda forces; then there was much strategic drift for several years, with the resurgent Taliban eventually seizing the initiative. They still hold it as American and NATO forces are leaving. The Iraq War was also begun with an impressive offensive, but insurgents soon began to dictate the course of events, and did so through late 2006. Thereafter, however, U.S. forces found a way to shift the momentum and the situation improved markedly — before they simply left at the end of 2011. In Libya, Qaddafi’s forces clearly held the upper hand until NATO’s intervention, after which they were almost completely on the defensive. Scores: Afghanistan, 4; Iraq, 7; Libya, 9.