In the aftermath of Ronald Reagan's death, many commentators have described George W. Bush as his political heir. In making that link, they are probably thinking of both men's tendency to describe foreign policy in moral terms, as a struggle against an "evil empire" or an "axis of evil."

But the comparison may go deeper. Beyond Reagan's rhetoric, he showed a pragmatic willingness to change course. That pragmatism was clear in his handling of foreign issues from Lebanon to the Soviet Union. And a similar pragmatism under pressure now seems to be gathering force in the Bush White House as the administration struggles to find an exit strategy from Iraq.

Reagan was a Protean leader, capable, like the Greek god, of changing form depending on political needs and circumstances. He talked tough but generally acted with restraint. That ability -- to combine an adaptive and often compromising political approach with the reassuring, changeless language of values -- was part of Reagan's political genius.

Reagan demonstrated his willingness to alter course in Lebanon. In a burst of nation-building enthusiasm, he had sent troops into that war-ravaged country in 1982. But after suicide bombers destroyed the U.S. Embassy and Marine barracks there in 1983, Reagan decided to cut his losses and evacuate American troops. The political damage was eased by Reagan's near-simultaneous invasion of the tiny Caribbean nation of Grenada.

The pullout from Lebanon was either an amoral retreat under fire or a prudent exercise of realpolitik, depending on your perspective. But politically, it was obviously a winner. Most Americans agreed with Reagan that Lebanon wasn't worth the cost in American lives. A somewhat more dubious example of the Reagan administration's realpolitik in the Middle East was the decision to trade arms to Iran to secure the release of U.S. hostages in Lebanon. When the secret deal became public, Reagan managed the political fallout partly by insisting he had done nothing of the sort.

Reagan's greatest achievement was to mobilize moralism and pragmatism in a way that eventually toppled the Soviet Union. He dared to reject the notion that the Soviet "evil empire" was a fact of life just because the Russians had nuclear weapons. Reagan backed up that commitment by fighting proxy wars in Nicaragua, Angola and Afghanistan. But by the late 1980s, he was engaging Mikhail Gorbachev in a web of agreements on arms control and human rights -- helping foster a process of change inside the Soviet Union that ultimately destroyed communist rule. Part of what made Reagan's principled positions viable was the fact that his key advisers were supremely realistic in carrying them out. That was certainly true of James Baker, who was Reagan's chief of staff and later treasury secretary, and of Colin Powell, who was Reagan's last national security adviser.

Bush's rhetorical style has, if anything, been even more unyielding than Reagan's. Bush's critics and supporters alike have tended to focus on this seeming inflexibility -- especially as America's difficulties in Iraq have mounted. But under the rubric of "stay the course," the Bush administration over the past several months has in fact begun executing a sharp change of course. One could almost call the adjustment of strategy "Reaganesque."

The pragmatic core of this new policy is evident: Where the Bush administration once disdained a role for the United Nations in postwar Iraq, it is now insisting on one; where it once talked of radical de-Baathification, it just engineered the appointment of an interim prime minister, Ayad Allawi, who is committed to bringing Baathists into the government and who is himself an ex-member of the party; after funneling tens of millions of dollars to Iraqi exile leader Ahmed Chalabi, it has now thrown him overboard.

The key policy changes seem to have come two months ago, when the administration was on the verge of launching what would have amounted to a new war in Iraq, against Sunni insurgents in Fallujah and Shiite followers of Moqtada Sadr in Najaf. Sensing the potential costs, the administration stepped back from that brink of confrontation -- and began focusing on ending the occupation. The architect of the revised Iraq strategy is Robert Blackwill, who is a deputy to national security adviser Condoleezza Rice and years ago was Rice's first boss when she served on the National Security Council staff of Bush's father. The new policy isn't always a pretty sight, and it involves some compromises of principle, but that's often the case with realpolitik.

Realism has become something of a dirty word for conservatives. But they should recognize that for all Reagan's bravado, he was a master of combining pragmatism and principle. In this, too, Bush may now be following his mentor.

davidignatius@washpost.com