Britain should cancel the presidents visit and join with allies to impose diplomatic and economic sanctions on the US, says foreign affairs commentator Simon Tisdall

Donald Trump's torpedoing of the Iran nuclear deal on highly specious and misleading grounds is an act of wanton diplomatic vandalism fraught with dangers. While the 2015 agreement may not yet be wholly sunk, it is holed below the waterline. Many in Tehran will see the sweeping reimposition of US sanctions as a declaration of war. As for Trump, he has once again proved himself the master of chaos.

This aggressive bid to further isolate Iran appears designed to ultimately enforce regime change. In the short-term it will destroy remaining reciprocal goodwill, undermine pro-western Iranian sentiment, empower hardliners, trigger an high oil prices crisis, and increase the risk of conflict centered on Syria and Israel. It creates the spectre of a regional nuclear arms race, and injuries the western alliance to the advantage, among others, of Russia. It is a Crimea-sized blow to the primacy of international law.

Yet Trump's short-sighted folly, far from being unprecedented, is entirely consistent with a long history of similarly disastrous Middle East policy missteps by previous US presidents. The region is littered with the corpses of momentously misconceived and wrong-headed US policies, spawned by the same noxious mix of ignorance and arrogance now permeating the White House. In this respect, Trump is no different from many of his modern predecessors.

Iran, as ever, is a case in point. The 1979-81 Tehran hostage crisis is usually referenced by those seeking to explain enduring, official US enmity. It's true America's national humiliation was considerable, and Jimmy Carter paid the political price. But the Iranian people's real offence was not the embassy siege. It was their presumptuous subvert of the shah's autocratic, pro-American regime in the 1979 revolution.

The US and the UK, after all, had gone to considerable difficulty in 1953 to keep Iran in line, covertly ousting its democratically elected government of prime minister Mohammad Mosaddegh. Their loss of influence, consequent on Ayatollah Ruhollah Khomeini's assertion of absolutist clerical rule, was the product of their own machinations. Here was the genesis of lethal US backing for Saddam Hussein in the 1980 -8 8 Iran-Iraq war.

The fight to repulse Saddam's invasion took 300,000 Iranian lives. Its expense, and causes, are not forgotten. Close by the Khomeini mausoleum south of Tehran, I once walked amongst the well-tended, shaded graves of hundreds of “martyrs” interred in Behesht-e Zahra cemetery. The war was a national trauma. Yet there has been no US apology , nor any thought of one. Although the US finally turned on Saddam in 1990, although Iran helped track al-Qaida following the 2001 assaults, and even though the nuclear bargain elicited significant concessions, venomously irrational, unmitigated US hostility persists.

Among the many US-fomented cataclysms in the Middle East, George W Bush's 2003 decision to invade Iraq without a plan was a standout moment, unrivalled in its strategic incoherence and staggering incompetence. It destabilised Iraq territorially and economically. Bush's” axis of evil” rhetoric and” global war on terror” fuelled sectarian violence and jihadism, playing midwife to Islamic State. And the ensuing, lengthy occupation failed to entrench inclusive democratic governance, as this weekend's Iraq elections may again demonstrate.

Ronald Reagan utilized covert Middle East arms sales to money an illegal war in Nicaragua in the 1980 s. Likewise, the US armed the Afghan mujahideen, then blanched as they morphed into the Taliban. George HW Bush liberated Kuwait in 1991 merely to betrays Iraq's Kurds and Shias when they demanded freeing, too.

Bill Clinton tried to end the Palestine-Israeli conflict, inspiring great optimism. I recollect standing on the White House's south lawn in 1993 as Clinton physically pulled Yasser Arafat and Yitzhak Rabin together for a reluctant handshake that had taken decades in coming.” Enough of blood and tears, enough … The time for peace comes in here ,” Rabin solemnly declared.

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