With the Cold War behind them, NATO members gathering here in Lisbon for a summit on Friday will seek to assert their continued relevance.
The future of the Afghan war effort will be a key part of the meeting's agenda, and the nations will also deal with missile defense of NATO territory. The alliance will also adopt a new mission statement, or "strategic concept."
The strategic concept will aim to reinvigorate the NATO alliance 20 years after the end of the Cold War. Calling Lisbon, "one of the most important summits in the history of our alliance," NATO Secretary General Anders Fogh Rasmussen hopes the new global outlook will prove the organization is still relevant.
"No other organization can marshal, deploy and sustain NATO's military power," Rasmussen said last month. "There will be other missions in the future for which only NATO can fit the bill. We will have to be ready."
In an op-ed article Friday in the International Herald Tribune, U.S. President Barack Obama said that the strategic concept recognizes "the capabilities and partners we need to meet the new threats of the 21st century. This must begin by reaffirming the lifeblood of this alliance - our Article 5 commitment that an attack on one is an attack on all."
Obama said alliance command structures need to be reformed "to make them more effective and efficient." He talked about investing "in the technologies that allow allied forces to deploy and operate together effectively, and develop new defenses against threats such as cyber attacks."
"To ensure that this commitment has meaning, we must strengthen the full range of capabilities that are needed to protect our people today and prepare for the missions of tomorrow," Obama wrote.