The U.S. has no diplomatic leverage because the military option is all but off the table. From all accounts, the Obama administration has dropped the "or else" alternative from its advocacy of sanctions, and is prepared to live with a nuclear Iran. Greg Sheridan from The Australian has an excellent piece on the subject:
So Israel has assumed the role of bad guy, and has taken the case directly to the Chinese that the choice is not between sanctions and no sanctions, but between sanctions and an Israeli attack. As reported by the Times of London:
US President Barack Obama has decided to abandon any serious effort to prevent Iran from acquiring nuclear weapons. He is determined instead to live with a nuclear Iran, by containment and, if possible, negotiation.
This is the shifting tectonic plate in the Middle East.
This is the giant story of the past few weeks which the world has largely missed, distracted by the theatre of the absurd of Obama's contrived and mock confrontation with Israel over 1600 apartments to be built in three years' time in a Jewish suburb in East Jerusalem.
Iran is the only semi-intelligible explanation for Obama's bizarre over-reaction against the Israelis.
Israel is not prepared to live with a nuclear Iran, unlike the Obama administration.
Israel will send its most senior military strategist to China this week to convince Beijing that it is serious about plans to bomb nuclear facilities in Iran if international sanctions fail to curb Tehran’s development of atomic weapons.
The visit, part of an intense round of diplomacy between China and Israel, follows signs that Beijing will shortly back tougher economic sanctions against Iran at the United Nations security council....
Diplomatic observers have been astonished by the pace of Israeli diplomacy in China.
Major-General Amir Eshel, who heads the Israeli army’s planning directorate, will fly to Beijing this week. Eshel, an air force pilot, will warn China of the international consequences of military action, particularly the potential disruption to oil supplies on which much of China’s manufacturing and international trade depend. Tougher sanctions, he will argue, are the lesser of two evils.
Last month Major-General Amos Yadlin, the head of Israeli military intelligence, was dispatched to Beijing with the latest information about Iran’s progress towards making a nuclear device, which some experts believe could be achieved later this year.
“Yadlin was given Prime Minister Benjamin Netanyahu’s personal permission to release Mossad’s latest evidence about Iran’s progress towards testing nuclear warheads, enriching uranium and adopting their Shahab missiles to carry nuclear warheads,” said a source.
In a move described as “incredibly rare”, China sent a general to Tel Aviv last week to inspect the Israeli air force’s strike capabilities. Military relations between the two countries have been strained since a deal to export Israeli-built early warning aircraft to China collapsed under American pressure in 2000.
Given that Israel, at a minimum, would need for the U.S. to look the other way as Israeli planes flew towards Iran, I'm not so sure the Israeli threat remains credible after the events of the past few weeks.
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