Whether Americans realize it or not, the United States has just declared war on Iran. And, in part because the declaration was less than clear, that could be even more dangerous than it sounds.

The U.S. transformed a long-simmering proxy tit-for-tat between the two sworn enemies to one of direct military confrontation.

When the U.S. on Friday assassinated Qassem Soleimani, a top Iranian general who directed violent anti-U.S. campaigns for more than 15 years, it transformed a long-simmering proxy tit-for-tat between the two sworn enemies to one of direct military confrontation — one to which Iran will have almost no choice but to react to forcefully (and has indeed already promised “revenge”). This could easily mean targeting U.S. troops in the Middle East, as well as U.S. embassies and military facilities farther afield, and American cyber assets throughout the world. It could also lead to attacks on U.S. allies such as Saudi Arabia and Israel, which carries with it the risk of a wider regional conflagration.

What all this gains us is unclear. Nothing suggests the killing of Soleimani, who commanded Iran’s powerful Revolutionary Guards’ Quds Force and was on a trip to Iraq, is part of a well-planned strategy to bring Tehran to its knees, or to the negotiating table. The United States has toggled between both of these aims in its long, drawn-out struggle with Tehran, and there’s no sign this contradiction has been resolved.

Until now, the Trump administration’s strategy of “maximum pressure” on Iran — pulling out of the nuclear deal while ratcheting up sanctions and other forms of U.S. pressure — seemed driven by the goal of forcing some sort of peaceful accommodation with Tehran over its nuclear program and regional policies, but this abrupt escalation has cast all that into doubt and led both the U.S. and Iran into dangerous and uncharted waters. Cooler heads, on both sides, may prevail, with the immediate prospect of hot conflict cooling into a colder war. But the game seems to have been significantly changed.

Get the think newsletter. This site is protected by recaptcha

Among other perils, the move suggests the U.S. hasn’t yet thought out its endgame: Where does it want to be at the conclusion of all this? What does it want to accomplish? What U.S. contingency plans are in place for when things, inevitably, go off course? The fact that these questions are apparently unanswered means that all the regular risks of undertaking war, especially in the tinder box of the Middle East, are exponentially more dangerous because of the impulsive approach President Donald Trump has taken here.

And then there’s the matter of what course the war takes in the short-term. What costs, for instance, is the U.S. prepared to suffer? That question generally guides strategy and cost-benefit analysis in waging a campaign. But we have no indication that Trump has evaluated this issue or is operating under a guiding principle of what consequences will and won’t be tolerated. Previous wars, and even limited regional conflicts, almost invariably have come after lengthy planning efforts, some years in advance, to sort out strategies and outcomes favoring U.S. interests (and generally were accompanied by information provided officially or unofficially by the Pentagon that made these efforts clear, much in contrast to Friday’s attack).

That isn’t to say there was no justification for the assassination. The Defense Department said in a statement about the killing that Soleimani “was actively developing plans to attack American diplomats and service members in Iraq and throughout the region” and blamed him for a recent string of attacks on U.S. bases in Iraq, including a Dec. 27 strike in Iraq that killed an American contractor. Trump also blamed Iran for a militia-led attack on the U.S. Embassy in Baghdad Tuesday that forced U.S. diplomats to hole up in safe areas.

So there’s no doubt he deserved his fate, as I learned during my tenure on the National Security Council Iraq staff in 2005-07. The U.S. State Department estimates Iran — largely under the leadership of Soleimani’s Quds Force — was responsible for the deaths of 603 American troops since 2003, accounting for 17 percent of all deaths of U.S. personnel in Iraq from 2003-11.

But in waging war, that’s not enough. The U.S. needs to be smart, not just right. There’s no doubt that whatever the utility of taking out an evil man, the overall goal for the U.S. should be to strengthen, not weaken, its position in the Middle East. Yet within hours of the U.S. action, Iraqi legislators upped their demands that U.S. troops (now numbering around 5,000) should be voted out of the country, demands that the lame-duck Iraqi prime minister has reluctantly acceded to. Massive protests by Iraqis against government corruption and Iranian schemes to control their country are now likely to turn decisively against the United States, which had just recently enjoyed a brief opportunity to profit from Tehran’s mistakes.

And then there’s the matter of Iranian retaliation. It will most likely utilize its militia allies in Iraq to step up attacks on bases where the U.S. maintains a presence, and potentially attack American air and ground movements with the country. Combined with political pressures from the enraged Iraqi legislature and public, this could quickly make the U.S. presence in the country untenable.

Iran will also choose less obvious battlefields, along the lines of the murderous bombing of the U.S. facility in Khobar Towers, Saudi Arabia, in 1996, or the bombing of the U.S. Marine barracks in Beirut, Lebanon, by the Iranian-backed Hezbollah in 1983. American personnel and their families in Europe and elsewhere may not be immune, either, if past is prologue.

In short, Iran can be expected to respond asymmetrically, using terror networks, militia proxies, and deniability to wreak havoc on the U.S. diplomatic and military machine in the Middle East. It will seek to dictate the terms of its battle with U.S. — the places, the timing and the tactics — hoping to keep America off-balance in an election year and calculating that the pain it can inflict will be disproportionate to any gain the U.S. might expect from this new war.

Ironically, Washington’s best hope for overmatching Tehran and bringing the conflict to a successful end may lie in expanding the war to include conventional military targets and force-on-force confrontations, where America’s superior technology, weapons and strategic depth can come into play and prevent Tehran from dictating this war’s script.

Iran can be expected to respond asymmetrically, using terror networks, militia proxies and deniability to wreak havoc on the U.S. diplomatic and military machine in the Middle East.

By playing to Tehran's weaknesses, the United States may best be able to limit loss of life and create a situation in which negotiations, perhaps brokered by the European Union or a trusted Arab go-between with deep ties to Iran, such as Oman, could lay the groundwork for a halt to hostilities and maybe even the basis for a new diplomatic deal. Whether the administration's endgame includes such a strategy or is simply reactive its still unclear.

American leaders have known how to make the best of a tough situation before. As General Dwight D. Eisenhower is believed to have said of his World War II game plan, “Whenever I run into a problem I can’t solve, I always make it bigger.” The Trump administration has certainly done just that. We can only hope that what comes next will enjoy something of Eisenhower’s success.

Related: