When it comes to foreign policy, John F. Kerry is no John F. Kennedy.

In his 1961 inaugural address, the 35th president of the United States declared that Americans would “pay any price, bear any burden” in their ongoing defense of liberty and human rights “at home and around the world.” Like other presidents before and since – Harry Truman, Ronald Reagan, George W. Bush – JFK believed that it was America’s destiny to advance freedom and democratic self-government, and oppose the world’s tyrants. This is the “idealist” approach to US foreign policy.

Kerry sees America’s role differently. For nearly half a century, the man poised to become the 68th secretary of state has generally frowned on the belief that American muscle should be flexed in order to promote liberal democracy. As early as 1966, Kerry wanted America to lower its profile on the international stage.

“What was an excess of isolationism has become an excess of interventionism,” he said in a speech at his Yale graduation. It was one thing to defeat Nazi Germany, but that didn’t mean America had to try to win the Cold War too. “The United States must, I think, bring itself to understand that the policy of intervention that was right for Western Europe does not and cannot find the same application to the rest of the world.”

There have been exceptions. Kerry originally supported the 2003 invasion of Iraq, and last year backed a no-fly zone in Libya to prevent Moammar Qaddafi from slaughtering the civilians rising against him.

But on the whole, Kerry prizes order and stability over liberty and human rights. He prefers to accommodate and engage America’s foes than to deem them enemies who must be defeated. He thought the horrors of 9/11 justified not a military war on terror, but only better “intelligence gathering, law enforcement, public diplomacy.” During his run for the White House in 2004, Kerry told The Washington Post that “as president he would play down the promotion of democracy” – not because he denied the lack of freedom in places like Pakistan, China, and Russia, but because other issues “trumped human rights concerns in those nations.”

Again and again, Kerry has shown a remarkable indulgence toward the world’s thugs and totalitarians. Within months of becoming a senator in 1985, he flew to Nicaragua in a show of support for Marxist strongman Daniel Ortega, a Soviet/Cuban ally; he returned to Washington talking up the Sandinistas’ “good faith.” More recently Kerry earned a reputation as Bashar al-Assad’s best friend in Congress. Against all evidence, Kerry described himself as “very, very encouraged” by the Syrian dictator’s openness to reform; he repeatedly flew to Damascus to visit Assad, describing him afterward as “my dear friend” and assuring audiences that engagement was working: “Syria will move; Syria will change as it embraces a legitimate relationship with the United States.” By the time Kerry finally changed his tune, thousands of Syrian protesters were dead or behind bars.

Kerry’s foreign policy views – like those of President Obama – are typical of the so-called “realist” school, which regards considerations of human rights or democracy as a sentimental distraction from the ruthless business of power-balancing and national self-interest. President Nixon and the first President Bush were firmly in the “realist” camp, too. “I have enormous sympathy for the foreign policy of George H.W. Bush,” Obama said as a candidate in 2008. And indeed, his reluctance to speak out when pro-democracy protesters were being bloodied in the streets of Iran in 2009 was strikingly reminiscent of Bush the elder’s refusal to protest China’s savage crackdown on democracy activists in Tiananmen Square 20 years earlier.

Both realism and idealism have a role to play in US statecraft, but the problem with the “realist” approach is that it too easily slips into callousness. Autocratic regimes may brush off mass murder or violent repression as other countries’ “internal affairs,” but such coldness is unworthy of the United States.

“I am very high on John Kerry,” says Brent Scowcroft, who was national security advisor to Bush 41 and remains a prominent “realist” exponent. “He is not beset by illusions or campaigns on behalf of abstract principles. His instincts are solid.”

If only they were. As Kerry’s prolonged willingness to defend a monster like Assad suggests, however, his “realist” instincts are all too fallible. Of course idealists make mistakes too. But the next secretary of state might bear in mind what that other JFK understood: American foreign policy is most truly realistic when it is rooted in the ideals that have made America such a beacon.

(Jeff Jacoby is a columnist for The Boston Globe. His website is www.JeffJacoby.com).