Now they have their Joan of Arc. Those who have long claimed that the sinister, shadowy forces of "the Israel Lobby" pull the strings of US foreign policy at last have a martyr. Last week Charles Freeman, a former diplomat, said he would not take the job he had been offered, chairing the US National Intelligence Council: he had, he said, been the victim of a campaign of "character assassination" conducted by an "Israel Lobby [willing to] plumb the depths of dishonour and indecency". In a furious statement, he declared that the "aim of this Lobby is control of the policy process".

Those who in 2006 lapped up the thesis argued by the US academics John Mearsheimer and Stephen Walt, attributing to the mighty lobby the power to divert the US from its own interests, seized on Freeman's fall as decisive proof. Walt himself declared: "For all of you out there who may have questioned whether there was a powerful 'Israel lobby'," he blogged, "think again."

As the reception to the original Mearsheimer-Walt article showed, this is radioactive terrain. Those who wade in carelessly can find themselves burnt. The explanation is not complicated. The notion that Jews wield excessive power, and do so in mysterious ways; that they advance the interests of a foreign power; that they function as some kind of fifth column, and that as such they have often led their country into needless wars - all these are accusations that have been hurled at Jews going back many centuries. It should be no surprise that Jews' ears prick up if they think they can hear these old tunes hammered out once more.

And yet, after several conversations with Israel supporters in both Washington and Tel Aviv, I have found no one who denies that Freeman was indeed the victim of advocates for Israel. It is quite true that many on Capitol Hill disliked Freeman's devotion to Saudi Arabia, the country where he had once served as US ambassador: he recently suggested King Abdullah be renamed "Abdullah the Great". True, too, that a critical blow came from Nancy Pelosi, the house speaker, reportedly outraged by Freeman's overly indulgent attitude towards China's rulers. But I'm reliably told that these lines of attack originated with the pro-Israel crowd. Nor have Freeman's character assassins bothered to hide their fingerprints.

On the contrary, several have bragged about their role, among them Steve Rosen, a former official of the American-Israel Public Affairs Committee, or Aipac, who launched the attack on Freeman.

Surely, then, as Walt claimed, this settles not only the Freeman whodunit but the larger question of the mighty "Lobby". Clearly it is every bit as vicious - and effective - as its detractors have claimed, able to derail even a new and popular administration such as Barack Obama's simply because it had the temerity to pick a man who had, among other things, condemned the Israeli occupation as "brutal oppression" - right? Not quite.

The flaws in the Mearsheimer-Walt case remain as visible as when they were exposed by the Palestinian-American scholar Joseph Massad, Noam Chomsky and a clutch of other anti-Zionists. For one thing, if Israel and its backers really did control United States foreign policy, there would never be any divergence between them: Washington would simply do "the Lobby's" bidding. But that is hardly the case. One can go back to the mid-1980s, when Israel and its friends begged the Reagan administration not to sell Awacs surveillance planes to Saudi Arabia - to no avail: the Saudis got their planes. Or spool forward to 1991 when George Bush pressured Israel to attend a peace conference against its will and withheld $10bn in much-needed loan guarantees unless Israel agreed to freeze settlements on occupied land. You might mention Israel's proposed arms sales to China: Washington compelled Israel to back down, first in 2000 and again in 2005. More awkwardly, Israel has long sought the release of those who spied for it against the US. Washington has consistently refused.

Chomsky asks a useful question. If the US has been led to behave the way it does in the Middle East by the cunning "Israel Lobby", how come it behaves the same way elsewhere? "What were 'the Lobbies' that led to pursuing very similar policies throughout the world?" As for the Middle East, Chomsky quotes the scholar Stephen Zunes: "There are far more powerful interests that have a stake in what happens in the Persian Gulf region than does Aipac [or the Lobby generally], such as the oil companies, the arms industry and other special interests whose lobbying influence and campaign contributions far surpass that of the much-vaunted Zionist lobby ..."

The naive assumption at work here is that the American dog has no interests of its own, leaving it free to be wagged by the pro-Israel tail. It's a convenient view, casting the great superpower as a hapless, and essentially innocent, victim. But guess what: the US emphatically does have its own strategic interests - oil chief among them - and it guards them fiercely. Support for Israel as a loyal, dependable ally - ready to take on Arab and other forces that might pose a threat to those interests - has served America's purposes well. That's why the US acts the way it does, not because Aipac tells it to.

Perhaps the most powerful example - if only because so many believe the reverse to be true - is the Iraq war. Plenty of Mearsheimer-Walt followers reckon it was the "Lobby" wot done it: it was Israel that pushed for war. But as Lawrence Wilkerson, former chief of staff to Colin Powell, and others have explained, Israel's leaders in fact repeatedly warned against an attack on Saddam, fearing it would distract from, and embolden, what it regarded as the real threat, namely Iran. As it happened, they were right.

So the myth of an all-powerful Israel lobby, pulling the strings, is a delusion. But it's equally false to pretend that Aipac and its allies don't exist or exert genuine influence. They do and they play hardball, as the Freeman affair has vividly demonstrated. (Indeed, the negative publicity that has resulted may make this victory a pyrrhic one.)

Viewed this way, clearly and through a lens unclouded by exaggeration and mythology, they are to be strenuously opposed. Their attempt to limit the voices heard in Washington is not just an offence against pluralism, it also hurts the very cause Aipac purports to serve: Israel.

Aipac's approach - not so much pro Israel as pro the Israeli right wing - ends up pushing US politicians away from the policies Israel itself needs, specifically the dialogue with enemies and territorial concessions that are necessary if Israel's long-term future is to be secured.

The good news is that alternatives are emerging. Founded last year, J Street styles itself as a "pro-Israel, pro-peace" advocacy organisation, thereby creating a space for those US politicians who support Israel but believe the policy of recent Israeli governments is hurting Palestinians and imperilling the future of the Jewish state. Aipac and its allies have had the monopoly on Israel advocacy for too long. Let's hope the Freeman episode prompts America's leaders to take a hard look at them, to see them as they really are: not all-powerful - and not always right either.



freedland@theguardian.com