The Franco-American-British coalition leading military intervention in Libya has demonstrated the cardinal rule of international security: enduring alliances matter. Ultimately, when the chips were down and the rebel stronghold in Benghazi was under threat, it was a coalition of long-standing allies that rallied behind one another to enforce a no-fly zone over Libya.

British Prime Minister David Cameron quickly emerged as Europe’s unofficial leader on the issue of Libya and was among the first to call for Libya to be suspended from the U.N. Human Rights Council. French President Nicolas Sarkozy also took an early leading role, and, working with Cameron, successfully rallied international support for military intervention at the Paris Summit on Saturday. The coalition now stands at 10 nations—the vast majority of which are already solid allies with one another, and nine of which are working together in Afghanistan.

The EU has not had a clear voice on this issue. Crucially, EU Foreign Minister Lady Catherine Ashton tried to act as a spoiler by telling Prime Minister Cameron to “hold his horses” over military intervention—even though Lady Ashton has presided over a slew of failed policy initiatives to promote human rights and democratic reforms in Libya and other parts of North Africa and the Middle East. Going forward, it is important that instead of delving into areas where she has no legitimacy, Lady Ashton focuses EU action in the areas where Brussels has a genuine role to play—enforcing strict sanctions on Libya until Qadhafi steps down; reforming EU aid programs so that aid is linked with verifiable improvements in human rights; and effectively promoting democracy.

It is unclear whether NATO will play a wider role in Libya beyond its current enforcement of the Libyan arms embargo. NATO may end up being in the lead, or it may simply provide operational support such as surveillance or command-and-control capabilities. The alliance has not yet reached a consensus on NATO’s future role, and it is likely that heated debate will persist in the North Atlantic Council.

However, while the ISAF mission in Afghanistan demonstrates that NATO will sometimes be the most appropriate vehicle for multinational military action, it doesn’t mean that NATO is the only option for such operations. And regardless of NATO’s future involvement, the principle stands that building strong alliances requires a proactive strategy that strengthens trust, confidence and military cooperation between individual nation-states. Multinational cooperation should be seen as a complement to bilateral relationship-building and not a substitute for it, because when facing real challenges, nations turn to other nations with which they share trust, confidence, and a common view of what needs to done.