President Barack Obama's administration signed an agreement with Iran in 2015 placing strict limits on Tehran's development of nuclear technology. In return, Washington lifted some of the most punishing sanctions on the country. Three years later, however, President Donald Trump reneged on the deal.
Now Iran suffers the worst of both worlds. The US has again intensified the sanctions regime while demanding that Tehran renew the deal on worse terms - and with no promise, according to US Secretary of State Blinken, that the next US administration won't tear up the agreement anyway.
US "credibility" does not depend, it seems, on Washington being required to keep its word.
In the background, as ever, is the threat of joint military reprisals from Israel and the US. In October, Biden reportedly asked his national security adviser to review Pentagon plans for a military strike if this one-sided "diplomatic process" failed. A month later, Israel approved $1.5bn for precisely such an eventuality.
Washington's emphasis on its "credibility" is actually a story the US elite tells itself and western publics to obscure the truth. What is really prized is America's ability to enforce its economic interests and military superiority unchallenged across the globe.
After the Korean and Vietnam wars, and the US overthrow of the elected government of Iran to reinstall its dictator-monarch, there is barely a corner of the planet where the US has not meddled. In Lebanon, the former Yugoslavia, Iraq, Libya, Syria and its so-called "backyard", Latin America, US "credibility" has required interventions and war as an alternative to diplomacy.
In October 2019, as Trump suggested that US troops would be pulled out of Syria - where they had no authorisation from the United Nations to be in the first place - Leon Panetta, a former defence secretary and former head of the CIA, observed that the decision had "weakened the US" and "undercut our credibility in the world".
He added: "There isn't an ally that we've around the world that doesn't now distrust us and worry about whether or not we will stand by our word."
But this kind of credibility is built not on principle, on respecting others' national sovereignty, or on peace-building, but on the gangsterism of a superpower drunk on its own power and its ability to intimidate and crush rivals.
Washington's "word" is only selectively kept, as its treatment of Russia and Iran highlight. And enforcement of its "credibility" - from breaking commitments to threatening war - has had a predictable effect: they have driven Washington's "enemies" into an opposition camp out of necessity.
The US has created a more menacing adversary, as Russia and China, two nuclear powers, have found a common purpose in asserting a countervailing pressure on Washington. Since the late summer, the two have held a series of war games and joint military exercises, each of them a first.
The world is entering what looks like a new, even more complex cold war, in which any misunderstanding, mishap, or false move, could rapidly escalate into nuclear confrontation. If it happens, the pursuit of US "credibility" will have played a central part in the catastrophe.
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