“When one begins with an initial error,” Aristotle wrote in Book V of “The Politics,” “it is inevitable that one should end badly.”

Almost 17 months into his presidency, things are going badly for President Obama on multiple fronts. That is in part because he entered office with, and has governed based on, several initial errors. Among them are these:

1. Barack Obama entered office believing that when it came to international relations, opposition to America was largely the result of the personality and policies of his predecessor. Stalemates and conflicts were caused by the inflexibility and confrontational approach of George W. Bush. Obama would turn the page through diplomacy. Indeed, virtually every time he was asked about a thorny foreign policy issue during the campaign, Obama offered talking with the other side as the solution. Regimes like Iran and Syria would amend their ways once their leaders were exposed to the personal diplomacy of Obama. In the spirit of the prophet Isaiah, we would reason together.

Columnist Charles Krauthammer years ago referred to this attitude as the “broken-telephone theory of international conflict” — the belief that talking to other nations would untangle all the knots and clear up all the misunderstandings. Worse, Obama — like Jimmy Carter before him — believed that we could alter the ambitions of our adversaries simply by being more “reasonable,” more compliant, and less confrontational. Concessions would beget concessions; good will would beget good will.

It hasn't turned out that way. Obama's extended hand has been met with clenched fists. His worldwide American apology tour has been met with disdain. Iran particularly has become more intransigent, more aggressive, and more brutal since Obama was sworn in as president. We have no progress to show for his efforts. Quite the opposite. Obama is viewed as irresolute and unreliable by our enemies (including Iran, Syria, Venezuela, Cuba, and North Korea), by our competitors (like Russia and China), and by our allies (like Israel, Brazil, Honduras, Poland, the Czech Republic, Georgia, India, the United Kingdom, and even Afghanistan). There have been “Obama the Impotent” headlines in Europe. Even the president of France is asking of Obama, “Is he weak?”

Today America is in a more feeble position and our relations with allies and adversaries are generally in worse shape than they were pre-Obama presidency.

2. Barack Obama assumed office in the aftermath of the near-collapse of our financial system. The debt and deficit skyrocketed to record post-World War II levels. But rather than addressing this fiscal crisis, Obama used it to push through a sweeping liberal domestic agenda, most especially the federal government's unprecedented involvement in our health care system.

“A crisis is a terrible thing to waste,” Obama's chief of staff Rahm Emanuel said. What they did instead was compound the crisis. Obama's agenda has made our fiscal situation significantly worse, with the debt estimated to double in five years and triple in ten years. To borrow an analogy first used by C.S. Lewis, Obama, facing a flood, reached for a fire hose.

This error, in turn, was rooted in yet another false assumption: That Obama's election marked a significant ideological shift within the electorate. The president and his aides believed the public wanted the federal government to increase its size, cost, and reach. Obama and his team thought that in the aftermath of his election and in light of the circumstances he faced, trust in government would increase. Actually, trust in government was fairly low when Obama took office — and his attempt to create a new progressive era has eroded it further. Today the public's trust in government is near an all-time low. And Obama's signature domestic initiative, the health care reform bill enacted in March, is unpopular.

3. Barack Obama was the least experienced and least prepared chief executive in our lifetime. Yet he began his presidency having made extravagant promises, even by the standards of a political campaign. His ascension to power would mark a moment when the earth would begin to heal and the rise of the oceans would begin to slow. Millions of new jobs would be created, cities rebuilt, farms saved, lives mended. America's image in the world would be restored. Our politics would be transformed. Bipartisanship would rule the day.

Instead, Obama looks impotent on everything from closing Guantanamo Bay to the oil spill in the Gulf of Mexico, from stopping Iran's march toward nuclear weapons to solving the Israeli-Palestinian conflict. During the Obama era, America is more, not less, polarized. The partisan divide is growing rather than receding. Sleazy backroom deals are more rather than less common. Millions of jobs have been lost rather than added. Unemployment has gone up rather than down. The country is becoming more conservative, not more liberal. And the Democratic Party is running away from Obama's agenda rather than embracing it.

The man who campaign aides referred to as the “Black Jesus” is not only imperfect — all of us are — he at times looks overwhelmed and overmatched. There is now talk about a failed presidency, a Carter redux, and a political massacre for Democrats in November.

Barack Obama, a bright man in possession of undeniable talents, can still turn things around. But doing so will require that he recognizes the errors of his ways, that he alter the course and direction of his administration. If he doesn't, his presidency will end badly, for reasons Aristotle wrote all those years ago.

Peter Wehner is a senior fellow at the Ethics and Public Policy Center in Washington, D.C. He served in the Bush White House as director of the office of strategic initiatives.