The Chicago NATO Summit will be taking place against the backdrop of an almost irresistible tendency of U.S. retrenchment from Europe and the wider Middle East. The United States has already pulled back its troops from Iraq. The engagement in Afghanistan is slated to come to an end in 2014. Washington seems to have found the formula for limiting the scope of its engagement even under crisis conditions. As the Libya operation has demonstrated, “Leading from behind” seems to have caught the attention and support of many in the U.S. administration. For many, the Chicago summit will signal the end of the transatlantic dominion and usher in the much heralded “Pacific Century”.

As America’s attention drifts westward,  European attention is turning inwards. The eurocrisis is sapping many EU leaders’ political capital. There is very little talk about the security partnership with the United States. On the contrary, in Europe, the focus is on assessing the impact of current and future austerity measures on regional and global security.

Against this backdrop, the success of the Chicago Summit is likely to be determined by its ability to cement the transatlantic partnership. The Chicago Summit has to address the consequences of this unfavorable environment. It should conclude with a stronger than expected commitment to the transatlantic partnership.

The second measure of success for Chicago can be whether the Allies will achieve unity of vision for the future of the Alliance.

Since the end of the Cold War, NATO has been able to take advantage of two fundamental dynamics: enlargement and large scale operations. This era has now ended. There is no enlargement on NATO’s near term agenda. The few aspirant countries will not fundamentally alter this reality. Also large scale operations—Kosovo, Afghanistan—are likely to be absent from NATO’s playbook in the foreseeable future. As a result, the Alliance needs to find a new dynamic to maintain its cohesion.

The answer was tentatively given in Lisbon. The new Strategic Concept in effect maps the future of the Alliance. But the task in Lisbon was relatively easy. It involved long term objectives around which a consensus among the Allies was created. The task awaiting the Alliance leaders in Chicago will be different and possibly more challenging. They will have to devise the means for implementing the Lisbon vision. In other words, Chicago will have to be about how the Alliance can become what it decided to be in Lisbon.

It is from this perspective that key issues, such as smart defense, acquire significant relevance. Smart defense, as championed by Secretary General Rasmussen, is set to represent one of the most visible yardsticks for Chicago’s success. Smart defense is presented by the NATO leadership as the way forward for NATO. It is seen as the answer to many old and new problems that have and continue to bedevil the Alliance. Burden sharing between America and Europe can possibly be redressed by smart defense. The impact of the austerity measures can arguably be managed by smart defense. The generation of new and complementary capabilities can also be addressed by smart defense. It is no coincidence therefore that the concept of smart defense has figured prominently in the public speeches of NATO’s leadership. So it will be interesting to see to what extent NATO leaders will be able to commit themselves to a secure future for smart defense.