The news went off like a bombshell in Middle East politics: Israeli Prime Minster Ariel Sharon quit the right-wing Likud party he helped found three decades ago to form a centrist party called “Kadima” (in English, the term means "forward").

Its impact may reverberate in unexpected ways across the ocean — Sharon’s action provides a powerful example of how centrist politics might evolve in the U.S. if the moderate majority in this country continues to be held hostage by professional partisans on the left and right.

Sharon’s departure was not spurred by the frequent fights with the far right of his own party — fights which have occurred since his “Nixon in China” decision to embrace the American-led two‑state solution and subsequent withdrawal from the Gaza settlements.

Instead, his course became clear when left-wing members of the opposition Labor Party rejected the leadership of moderate statesman Shimon Peres in favor of the old school left-wing union leader Amir Peretz. (It is now believed Peres will join Kadima as well.)

This brought enthusiastic shouts from left-wing ideological purists, but it alienated moderate Labor Party members who had formed the national unity government with Mr. Sharon after the 2003 national election. Facing a likely parliamentary showdown from splinter-groups on the left and right, Sharon saw an opportunity to liberate Israeli politics from the influence of special interests.

Mr. Sharon has long been the most prominent hawk in Israeli politics, the general who gave no quarter to terrorists and their apologists in the past. But instead of being an ideological purist, he is a tough-minded pragmatist who prefers to make tactical decisions based upon “facts on the ground” rather than political theory.

Now hard-liners are quick to call him a traitor, while Sharon is applauded by the broad public. Make no mistake: there are risks to Sharon’s course of action. For decades, moderates in the Middle East have been murdered by extremists on their own “side” in an attempt to derail the peace process, most notably Egypt’s Anwar Sadat — assassinated by Islamic fundamentalists — and Israel’s Yitzak Rabin, assassinated by a right-wing Israeli gunman opposed to the Oslo Peace accords.

Despite the risks, Sharon’s political strategy seems solid: initial polls after the announcement show “Forward” winning a hypothetical 33 seats in the upcoming March elections, supported by 14 moderate members of Labor and Likud including former Jerusalem Mayor and current Deputy Prime Minister Ehud Olhmert. Likud would unceremoniously drop from 40 seats to a paltry 15, indicating the relative balance of power even within Likud between its centrist and right-wing members.

Sharon’s insight is that while moderate Likud and Labor Party members may have been less organized and influential within their own parties, they constituted a majority within the electorate as a whole — especially if led by a popular national political leader.

But all this is happening a half a world away — what relevance does Sharon’s move have for U.S. politics? Plenty.

Current polls show centrists leading the 2008 presidential pack, most notably Rudy Giuliani and John McCain. Between them, they possess more than 50 percent of the Republican primary voter support, despite the fact that these two men are strenuously opposed by certain factions on the far right.

This indicates not only their appeal across party lines, but also the fact that the national Republican Party is not as rigidly right-wing on social issues as some activists might have us believe. Beneath the G.O.P bunting, there is a marriage of convenience between its libertarian and religious right wings whose logic is loosening. Libertarians have been largely shut out on issues ranging from out-of-control spending by congressional Republicans to the dramatic growth of government under the Bush administration. When you consider that there are few elements of modern society more hostile to libertarian values of individual freedom than the religious right, it is easy to see that unless a new balance of power within a big tent is established, a split may be inevitable.

At the same time, the far left is making yet another bid for control of the Democratic Party in the belief that ideological warfare is preferable to winning over the reasonable edge of the opposition. The Howard Dean/Cindy Sheehan crowd is no more representative of mainstream moderate Democrats than Tom Delay or Jerry Falwell is to most mainstream Republicans.

The reality is that centrist Republicans and moderate Democrats often have more in common than either group does with the more extreme members of their own party. Add to this the rising number of Independent-registered voters — whose ranks have increased an average of 300 percent over the last 10 years alone — and the fact that a staggering 85 percent of Americans believe we need more elected politicians who vote independently rather than along party lines (according to a May 2005 Harris poll) and you start to see the broad-outlines of support for a centrist Independent candidate in 2008.

If Democrats insist on nominating a candidate associated with the left-wing of their party, like Hillary Clinton, while Republican activists veto the nomination of a centrist such as Rudy Giuliani or John McCain in favor of an un-charismatic social conservative, for the first time in American history there could be a strategic opening for a successful Independent candidate for president. As with Sharon, the larger cause would be a leader with the freedom to pursue the national interest without being held hostage by special interests — moving the country not left or right, but forward.

John P. Avlon is a columnist and associate editor for the New York Sun, former chief speechwriter for Mayor Rudolph W. Giuliani, and author of Independent Nation: How Centrists Can Change American Politics (Random House, 2004). For more about John Avlon, visit his web site, Independent Nation.org