For the U.S., the crisis in Iran is the latest episode in a long, tortured history

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The complex, multidimensional 21st century factors that American officials are juggling in the wake of Israel’s attack on Iran might be best viewed through two towering 19th-century European figures.

One is Austrian Klemens von Metternich, the most important statesman of the period, whose wisdom can be captured in one of his aphorisms: “The events which can not be prevented, must be directed.”

Another is Otto von Bismarck, the unifier and first chancellor of Germany. He understood that, as he put it, “All treaties between great states cease to be binding when they come in conflict with the struggle for existence.”

Indeed, the latest Middle East conflict is a combination of events that could not be prevented (Prime Minister Benjamin Netanyahu’s steely determination to prevent Iran from developing a nuclear weapon) and the sense that countries sometimes find themselves in a struggle for existence (and here we apply a New Testament concept to countries whose identities are tied to the Old Testament and the Quran, now locked in a struggle both sides believe has reached an end-of-days moment).

Together these notions govern the American way forward in a volatile situation where bombs, missives and drones are flying across the region. Together they will shape the American response to Israeli pleas that the United States add American bunker-busting capabilities to Israel’s assault on Iran’s buried uranium enrichment facilities.

For the U.S., the greatest benefactor of Israel, and for Iran, which since the country’s 1979 revolution has considered the U.S. the Sheytan-e Bozorg (“Great Satan”), this current crisis is the latest episode in a long, tortuous relationship that is one of the most complex in the global diplomatic portfolio.

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“American relationships with China, Russia, Saudi Arabia, Egypt and others are basically straightforward, but the relationship with Iran has been very complicated,” said Gene Garthwaite, a Dartmouth College historian of Iran.

“American policy has always been to support some kind of democratic government there. But at the same time, the U.S. has always opposed any government coming to power that would challenge American geopolitical interests and compromise American interests on energy and, now, on nuclear weapons.”

Those complications grow out of the unusually tumultuous history of American-Iranian relationships.

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As far back as the early 20th century, the United States political tradition provided inspiration to those who, bolstered by the support of American missionaries in education and medicine, sought to create a democratic government in Iran, then known as Persia.

After the Second World War, the United States began to assume Great Britain’s role as the dominant player in the country. By 1953, in an effort to preserve Western oil interests, the United States, with the British, fomented a coup to overthrow prime minister Mohammad Mosaddegh and restore the Pahlavi family dynasty to power.

All those elements – particularly the remarkably persistent resentments growing out of the 1979 seizure of American diplomats as hostages – shape Washington’s relations with Tehran, tensions that have come into even sharper focus now that Israel has taken steps to stop Iran from proceeding with its enrichment of uranium to near weapons grade.

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Last week, for the first time in two decades, the International Atomic Energy Agency determined that Iran was defying its nuclear-nonproliferation obligations.

The American side is quietly backing Israel, giving the Jewish state a long leash, and may eventually provide more than moral support. Secretary of State Marco Rubio issued a careful public statement emphasizing that the Israeli bombing of Iranian nuclear sites was conducted without U.S. military assets or support, though it swiftly emerged that President Donald Trump had prior knowledge of the plans.

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Having established that separation, the Trump administration, some Republicans and most Democrats are asserting that Israel has the right to assure its survival by assuring that Iran does not develop nuclear arms.

In the wake of threats from Iranian Defence Minister Aziz Nasirzadeh, American officials repeatedly have warned Iran, and implicitly its client states and non-national groups such as Hamas and Hezbollah, not to target American assets in the region.

The Council on Foreign Relations estimates that the United States has 40,000 troops in the region, with the USS Harry Truman carrier strike force in the Red Sea, Coast Guard ships outside the Persian Gulf, a destroyer in the eastern Mediterranean Sea, and long-established American bases in Kuwait, Bahrain, Qatar and the United Arab Emirates.

At the same time, Mr. Trump continues to express hope that negotiations will bring about the result that Mr. Netanyahu seeks.

“It is still unclear where things are going to go, because there have been mixed messages from both sides in the conflict – and from the United States,” said Javed Ali, a University of Michigan national-security and intelligence specialist with experience in the U.S. Defense Intelligence Agency.

“President Trump’s tone has shifted. The question is whether the administration has concluded that while Iran is busy retaliating against Israel, real movement in negotiations may have to come another day while Trump navigates through a complicated Republican environment.”

That environment is itself a reflection of separate domestic American political tensions.

Some Republicans, including GOP lawmakers with strong MAGA identities, are wary of any international involvement at all. That sentiment often is expressed in terms of “forever wars.” The series of conflicts between Israel and its neighbours, dating to 1948, is an especially apt description of a “forever war.”

“The bottom line is we cannot be dragged into, inexorably dragged into, a war on the Eurasian landmass in the Middle East or in Eastern Europe,” Stephen Bannon, a former top Trump adviser still regarded as close to the President, said on his podcast last week.

The emerging American consensus might be summarized in another maxim from Metternich.

“For great evils,” said the diplomat, whose realpolitik served as a model for former U.S. secretary of state Henry Kissinger, “drastic remedies are necessary and whoever has to treat them should not be afraid to use the instrument which cuts the best.”