US Presidency
2009

These needs will be met only if we act boldly in the years ahead and if we understand that the challenges we face are shared and our failure to meet them will hurt us all. For we have learned from recent experience that when a financial system weakens in one country, prosperity is hurt everywhere. When a new flu infects one human being, all are at risk. When one nation pursues a nuclear weapon, the risk of nuclear attack rises for all nations. When violent extremists operate in one stretch of mountains, people are endangered across an ocean. When innocents in Bosnia and Darfur are slaughtered, that is a stain on our collective conscience. That is what it means to share this world in the 21st century. That is the responsibility we have to one another as human beings. And this is a difficult responsibility to embrace, for human history has often been a record of nations and tribes and, yes, religions subjugating one another in pursuit of their own interests.