What's on the agenda for this weekend's informal summit?

If one principle guided American diplomacy through the last half of the 20^th century, it was to keep in mind, at all times, the fears and interests of Russia—not to appease them, but to exploit, manipulate, and, yes, sometimes accommodate them—in the pursuit of advancing our own interests.

Tensions with Russia have been flaring—and the world is more chaotic than it otherwise would be—in large part because President George W. Bush and his top advisers lost sight of this principle.

Presumably, he'll try to bring it back in focus this Sunday and Monday at a summit with Vladimir Putin. They're meeting not at the ranch in Crawford, Texas, but at the Bush family compound in Kennebunkport, Maine. Will Dad sit in? (It wouldn't hurt.) Will old pal Brent Scowcroft just happen to drop by? (Less likely, but that would be interesting.)

At the start of his presidency, Bush the younger understood the need to line up pins with the Russians (if only for appearance's sake) before taking actions that affected their security. He wanted to embark right away on a missile-defense program, which meant abrogating the Anti-Ballistic-Missile Treaty, the 30-year-old centerpiece of U.S.-Russian arms control. But he knew he first had to assure President Putin that the move wasn't directed at Russia. So he flew to Europe and famously looked into Putin's soul. Meanwhile, Colin Powell, his secretary of state, negotiated the Moscow Treaty, which cut each side's arsenal of offensive nuclear arms and created a broad framework for bilateral cooperation. By the end of the year, when Bush finally did withdraw from the ABM Treaty, Putin barely shrugged.

Soon after the attacks of Sept. 11, U.S. and Russian officials exchanged intelligence on counterterrorism; Putin let the CIA use air bases in Uzbekistan as a staging point for the invasion of Afghanistan; he engaged in a "strategic energy dialogue" with U.S. oil companies.

How, then, did it happen that this spring, when Bush announced a plan to place a mere 10 anti-missile missiles in Poland and the Czech Republic, he set off a flurry reminiscent of the Cold War's darkest days? Russian officials decried the move as "destabilizing"; charges and countercharges flew like flame-darts; Putin not only likened America to Nazi Germany but threatened to re-aim his nuclear missiles at Europe.

As far back as March 2006, well before the flap over missile defenses, a task force of the Council on Foreign Relations concluded, in an 82-page report, that the "very idea of 'strategic partnership' "—the watchword of U.S.-Russian relations a mere four years earlier—"no longer seems realistic."

Since then, Putin has curtailed U.S. access to the Uzbeki air bases, revoked Exxon/Mobil's license to explore Sakhalin's oil fields, and talked of revoking the Reagan-era treaty limiting the presence of troops in Europe.

To some degree, a deterioration in relations was inevitable. Putin gave in to Bush back in 2001 in part because he had no choice. Russia's economy was in shambles, its leverage nearly nonexistent. Now, soaring oil and gas prices have revitalized its economy; Putin's instinctive (and domestically popular) nationalism has risen to the fore; the days of bowing to the West, for its own sake, are over.

In part, this is a backlash to Boris Yeltsin's reform years, which Westerners regard as a golden age but most Russians recall as an era of poverty, disorder, and humiliation. Russian history is rife with "times of troubles" followed by a strong ruler who restores national power. Putin sees himself, and is widely seen, as such a ruler.

Steven Sestanovich, the author of the Council on Foreign Relations' report (and the ambassador-at-large for the former Soviet Union during the Clinton administration), thinks a major turning point in this backlash occurred during the Orange Revolution in Ukraine. In the winter of 2004-05, pro-Russia authorities were caught rigging the ballots in Ukraine's national election; massive street rallies in Kiev sparked a revote, which the rightful, independent candidate won.

However, many Russians view the whole episode as a nefarious American plot. "Well-placed, well-educated Russians have told me the nuttiest things about the Ukrainian election," Sestanovich says, "all of them having to do with a conspiracy by George Soros and the CIA to destabilize Russia."