In deciding whether to invade Iraq, US President George W. Bush is guided by a view of the world as a battleground of good versus evil.
Admirers praise him for a clear vision that cuts through diplomatic doublespeak and moral ambiguities, but detractors say trying to run foreign policy like a Bible class may land the United States in a conflict with dangerous and unpredictable consequences.
"Some people like to sneer at Bush for what they see as his ignorance and naivete, because he sees the difference between good and evil in the world," said Danielle Pletka, vice-president for foreign and defence studies at the American Enterprise Institute, a think-tank that is home to several influential voices supporting an Iraq invasion.
"The idea that someone is a simpleton because he sees the United States as a force for good is insulting."
On the other side, Los Angeles Times columnist Robert Scheer recently wrote that it was time for Bush to forgo the "biblical allegories of good and evil and recognize that in the 21st century, smiting one's enemies is an elusive goal requiring patience and subtlety, as well as timely heroics."
Campaigning for the presidency in 2000, Bush never pretended to be a foreign policy expert but said his inability to remember the names of leaders of such nations as India and Pakistan was less important than his overarching vision.
Bush was hardly the first US president to take office without much foreign policy expertise.
"I don't think that ignorance is ever an advantage but the fact is that the US political system often brings presidents to the White House who don't know much about foreign policy," said Walter Russell Mead of the Council on Foreign Relations.
Some, like Jimmy Carter and Bill Clinton, immerse themselves in the details, eventually becoming experts in their own right. Others, like Ronald Reagan, stick to the big picture and leave the details to others. Both approaches have had their successes and failures.
"Character, competence, the ability to manage and to articulate your policy are clearly more important than expertise," said James Gibney, executive editor of Foreign Affairs magazine.
"It helps to have a vision of the way the world works. Experts can provide the expertise," he said.
Bush won almost universal praise for his response to the attacks on the World Trade Center and the Pentagon on September 11 when he rallied the nation and much of the world with bold rhetoric and firm resolve.
He spoke in words that every American could understand. Osama bin Laden, the Saudi militant accused of masterminding the attacks, was not merely an enemy - he was "the evil one." The war on terrorism, became, in Bush's words, "a struggle for civilization itself."
But Bush's efforts to extend that same unequivocal rhetoric to Iraqi leader Saddam Hussein have so far failed to strike the same response, although he is yet to make the case for an all-out war.
A Gallup Poll released on Friday found that support for an invasion of Iraq had fallen from 74 per cent in November to 53 per cent now.
Bush has also been unable to impose discipline on either his administration or his Republican Party, which both appear to have divided into pro- and anti-war factions engaged in an increasingly nasty public battle.
Few in the United States would dispute Bush's assertion that Saddam is evil. However there is already no shortage of voices pointing out the many risks and complications of an invasion.
Among them are: the danger of taking heavy casualties; of dragging US troops into a quagmire from which it will take years to emerge; of blowing a massive hole in the US domestic budget; of destabilizing the Middle East; of prompting Saddam to fire chemical or biological weapons at Israel; of stoking more Arab fury and more terrorism; of alienating important allies; and of encouraging other nations to launch their own pre-emptive attacks on enemies.
Bush admirers see parallels between him and Reagan, whom they believe paved the way to victory in the Cold War over the Soviet Union, which Reagan called the "evil empire."
But Bush has found it hard to impose a single standard on the world. He has berated some countries for their failure to practise democracy while turning a blind eye to others whose co-operation is essential to the war on terrorism, notably Pakistan and former Soviet republics in Central Asia.
"I think his foreign policy is fairly muddled. He's doing what many presidents have done in the past, applying different standards to different situations," said Gibney.
Bush's desire to cut through complications to the heart of an issue and emerge with a bold, strong stance has also been on display in the Arab-Israeli conflict, an immensely complex clash of competing rights and wrongs that stretch back for more than a century.
The president has come down firmly on the Israeli side, calling on the Palestinians to dump their leader Yasser Arafat, who Bush says is hopelessly corrupt, untrustworthy and implicated in violence. But words have not been followed up by much concrete action.