Yet, the disagreement among members over whether to participate in the Libyan mission also demonstrated that the goals and the commitment of the alliance often remain ambiguous and contentious. "[Afghanistan] was not a good example of solidarity within NATO—everybody pulling their weight ... although we did manage to get everyone to contribute. In Libya, that just went out the window. Only a third of the allies really contributed," Volker says.
Still, even with the challenges, NATO is the best alliance the United States has, argues Burns, and the past decade has indeed proven its worth. "Reality is, when you have 28 countries in one alliance, it's going to be a rare moment when all 28 agree to make the same effort. But as long as NATO is able to act collectively, that's still positive and it's still important. It's an important tool for U.S. foreign policy," he says.