WASHINGTON - Defeat can lead to defeatism, or it can lead to constructive rethinking. Which path will President Obama take after setbacks overseas?
By defeat, I do not mean, as some Obama critics would have it, that the U.S. president "lost Crimea." The bad guy there is Vladimir Putin, not Barack Obama, just as the bad guy in Syria is Bashar Assad.
There was no viable military option that could have discouraged Putin's invasion of Ukraine, and there is no military option to reverse it. Even the now-ridiculed "reset" of U.S.-Russia relations was worth a try; no one knew for sure whether then-President Dmitry Medvedev might offer a viable alternative to Putinism. Obama was right to test the theory.
But while Putin's annexation of Crimea is not Obama's fault, it does starkly illustrate that the world Obama confronts today is not the world he expected to lead.
The president came into office believing that military assets were a 19th-century measure of power, of dwindling relevance in the 21st century. He believed that diplomacy could solve problems that George W. Bush had ignored, created or exacerbated; that the eventual abolition of nuclear weapons was perhaps the United States' most important goal; that economic reconstruction at home had to take precedence over - and was a necessary prerequisite for - leadership abroad.
His policies have reflected these understandings: Total pullout from Iraq. An Afghanistan withdrawal schedule untethered to conditions on the ground. A hasty departure from Libya after helping to depose its dictator. No meaningful assistance to the opposition in Syria.
When democratic uprisings stirred hope from Tunisia to Egypt and beyond, some foreign-policy veterans, like former national security adviser Stephen Hadley, urged Obama to seize the unexpected opportunity and help support historic change. Obama stayed aloof, and the moment passed.
Obama judged the world safe enough to sharply decrease military spending, and Europe and the Middle East safe enough to justify a "pivot" to Asia. The debate in town was what mission NATO could possibly have once it pulled out of Afghanistan.
Most of all, Obama wanted to concentrate on what he called "nation-building at home." He told the United Nations last fall that promoting democracy and free trade in the Middle East was no longer a "core interest" of U.S. foreign policy.
The scaling back of ambition resonated with U.S. public opinion. But the effects have not been as hoped.
As the United States retrenched, the world became more dangerous.
China continued a traditional - 19th-century, Secretary of State John F. Kerry might call it - military buildup, accompanied by aggressive territorial assertions in East and Southeast Asia. Tensions built among Japan, the Koreas and China as all wondered about America's staying power. (The joke was that everyone in the world believed the pivot to Asia was real, except Asian allies, who saw little evidence of it.)
North Korea's nuclear buildup proceeded unchecked. Egypt's government is more repressive than in Hosni Mubarak's days - and less friendly to the United States. In 2013, freedom regressed in 54 countries, compared with 40 in which it advanced - the eighth straight year of net decline, according to Freedom House.
In Syria, Obama was confident two years ago that Assad's "days are numbered," as he told Jeffrey Goldberg in an interview in the Atlantic. "It's a matter not of if, but when." He periodically promised, but never delivered, substantial arms and training for moderate forces opposed to Assad.
Meanwhile, Assad's position strengthened, even as he brought about what a U.N. official calls "the greatest humanitarian disaster since Rwanda." Al-Qaida forces established havens from which they can threaten the United States and Europe, and they are spreading into Lebanon and Iraq.
Now Putin has engineered the baldest violation of state sovereignty since Saddam Hussein invaded Kuwait in 1990.
Obama has responded sensibly with sanctions aimed at Putin's inner circle and promises to bolster Ukraine. You can argue whether he has calibrated exactly right, but he has appropriately engaged with and led the United States' European partners.
But these are early steps - and they are also only tactical steps. As the administration refashions its policy toward a changed Europe, will it re-examine its broader strategy, too? Will Obama question his confidence that the United States can safely pull back from the world?
The instinctive White House response will be to head into the political bunker: to deny that it ever displayed isolationist tendencies while painting critics as wild-eyed warmongers. This reflexive belligerence is understandable given that Obama's political enemies will happily use overseas setbacks to score points.
But the stakes are too high to leave the debate in those trenches. Tempting as it may be, the United States doesn't get to choose between nation-building at home and leadership abroad; it has to do both. With almost three years left in his presidency, it's not too late for Obama to change course.
Fred Hiatt is The Washington Post's editorial page editor.