For the better part of a century, Americans have assumed we would always remain the world’s greatest power, regardless of which party or president occupied the White House. We were too important, rich and strong to falter, our democracy too wise to fail.

The economy’s unraveling this fall is but the latest grave reminder that nothing is guaranteed. In a few short years, we have squandered our resources and international prestige on an ill-advised war. Through blind faith in deregulated markets, our leaders have undermined the nation’s economic stability while recklessly creating a national debt of $10 trillion.

Americans need a clean and dramatic break from the derelict policies of George W. Bush. We desperately need a president who will restore our standing in the world and re-energize us at home by turning attention to issues that Bush ignored: the need for energy independence, the stagnant wages of the middle class and the lack of affordable health care.

Barack Obama will be such a president. He speaks to Americans’ yearning for renewal. He has the ability to restore America’s confidence and guide this country toward a more stable and secure future.

Not since John F. Kennedy has a presidential candidate so moved a young generation. His election would be historic. It would alter the perception that minorities are limited in what they can achieve; the world would see an America that not merely preaches racial equality but lives by it.

No candidate is perfect. Obama, 47, is a first-term U.S. senator. He has detailed positions on important issues but not sponsored much important legislation. He has never run an organization, although neither has Republican John McCain.

But those who dismiss his experience sell short a strong résumé and record of leadership.

Obama combines Bill Clinton’s intellect and capacity to grasp complex issues with the focus that Clinton lacked. He would run the White House with the discipline of his campaign, assembling around him smart advisers, starting with vice-presidential nominee Joe Biden.

In the Senate, he has served on the Foreign Relations Committee. As a state senator in Illinois, he represented a large and diverse constituency. As a community organizer, he helped solve problems facing working Americans. At Harvard Law School, where he was a brilliant student, and as a law professor, he developed impressive analytical and oratory skills.

Obama grew up in a multiracial household and came of age in a different generation from McCain. He has an intuitive understanding of a rapidly changing, interconnected world. McCain’s world view was shaped by the Cold War and Vietnam.

That is why Obama has been right, and McCain wrong, on national security issues such as opposing the Iraq war and now advocating a timed withdrawal. The difference between them is not, as McCain claims, one of resolve but of judgment.

McCain, 72, says he will better protect America from foreign threats. But his first major decision, choosing Alaska Gov. Sarah Palin for vice president, was reckless and put ambition ahead of national security. Palin is unqualified for the office; her folksy but not embarrassing showing in the vice-presidential debate doesn’t change that fact.

Scratch the surface of McCain’s populism, and you get a 26-year Washington politician whose views mirror Bush’s. He would name like-minded judges to the Supreme Court to overturn Roe vs. Wade. While he talks about energy independence and environmental protection, his record belies his words. He would continue a national addiction to oil. He would make permanent Bush’s tax cuts for the few; Obama would aim tax cuts at the middle class.

Economics is not McCain’s strong suit, as he has acknowledged and lately proven. The nation needs a president willing to curb derivatives (and a vice president who knows what they are). Given a voting record supporting deregulation, McCain would not change course.

Obama will rebuild the economy by investing in the right priorities: green technology, scientific research, education and health care. Some proposals need more thought. For example, raising the Social Security payroll tax on higher-income workers could stifle job growth because employers would have to match it. But his overall vision plays to Silicon Valley’s strengths and America’s ideals.

The differences between Obama and McCain are stark. Only Obama has the temperament, intelligence and ideas to set America right. We enthusiastically urge his election Nov. 4.