“Our relationship with our European allies and partners is the cornerstone of our engagement with the world, and a catalyst for global cooperation. With no other region does the United States have such a close alignment of values, interests, capabilities and goals…

As an alliance of democratic nations, NATO ensures our collective defence and helps strengthen young democracies. Europe and the United States are working together to prevent the spread of nuclear weapons, promote peace in the Middle East and confront climate change…

We are each other’s closest partners. Neither Europe nor the United States can confront the challenges of our time without the other…

NATO will also transform itself in Lisbon with a new Strategic Concept  that 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…

 We can resume practical cooperation between NATO and Russia that benefits both…we can make it clear that NATO sees Russia as a partner, not an adversary. We can deepen our cooperation on Afghanistan, counter-narcotics and 21st century security challenges — from the spread of nuclear weapons to the spread of violent extremism. And by moving ahead with cooperation on missile defense, we can turn a source of past tension into a source of cooperation against a shared threat…”

Full text – Barack Obama – President of the United States – Before Meetings in Lisbon.