James S. Robbins

Opinion columnist

Qassem Soleimani was a violent man who lived a violent life. The Iranian major general lived by the sword and died by the drone. Soleimani’s death was a long time coming, and it is chiefly mourned by those who are seeking a similar end.

We can dispense with questions over whether the attack that killed Soleimani was an illegal assassination as opposed to a legitimate act in the war on terrorism. The United States has been conducting such strikes for years, and President Barack Obama faced no serious pushback for using drones to prosecute the conflict.

The Iranian Revolutionary Guard's Quds Force that Soleimani commanded was a U.S.-designated foreign terrorist organization, which gave its members the same status as al-Qaida, the Islamic State or any other terrorist group. According to the Pentagon, Soleimani was actively planning attacks against American forces, something he had done many times. Those politicians who question whether President Donald Trump had the legal right to conduct the strike can suggest adding it as another article of impeachment, if they dare.

Iran raised the stakes

The criticism that this move was escalatory ignores the fact that Iran has been escalating conflict in the Middle East for years. Iran supports insurgent and militia groups in Yemen, Afghanistan, Gaza, Lebanon and Syria, among others. Iran, using Soleimani’s Quds Force as its spearhead, was responsible for more than 600 American deaths in Iraq from 2003 to 2011, 17% of all U.S. dead in that conflict. President George W. Bush's administration never adequately made Tehran pay, and the Obama administration was more interested in paying Tehran.

Trump had been a model of restraint in the face of increasingly aggressive moves against American allies and interests by Iran and its proxies. These included attacks on Saudi oil refineries and tankers in the Persian Gulf, as well as aggressive moves against Israel in Syria, which the Jewish state has been responding to ably with strikes of its own. Trump even called off a planned retaliatory mission last June, after Iranian forces downed a U.S. drone, so it’s difficult to argue Trump was looking for pretexts for war.

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But the red line for Trump is and has been attacks that threaten or take American lives. When an American civilian defense contractor was killed Christmas week by rocket fire in a Quds-backed Shiite militia attack near Kirkuk, Iraq, the United States mounted a punitive strike, killing 25. When members of the militia group attacked the U.S. Embassy in Baghdad, Trump immediately sent in Marine reinforcements. The president then issued a threat to Iran, to which the supreme leader, Ayatollah Ali Khamenei, responded that America “can’t do a damn thing.”

Soleimani's taunts, Trump's response

This was not simply a taunt; Khamenei employed an effectively official slogan that Ayatollah Ruhollah Khomeini used repeatedly against President Jimmy Carter during the 1980 hostage crisis. The implication of another election-year embassy takeover was plain, so when Soleimani brazenly traveled to Baghdad, Trump demonstrated that the United States can do things, and damn well.

Tehran now threatens revenge, of course, and it will likely seek it soon. Soleimani had boasted of Iran’s “power in the region and capability for launching asymmetrical war.” Force protection is critical to prevent another episode like the 1983 bombing of the Marine Corps barracks in Beirut. And there is also the possibility of an Iranian-backed domestic attack, like the planned bombing, according to U.S. officials, in Washington, D.C., which was broken up in 2011.

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"We are near you, where you can't even imagine,” Soleimani had said. But it is safe to assume that any attack on the American homeland that was traceable to Tehran would be met with a significant, 9/11-style response. Despite Tehran’s bluster, the United States maintains escalation dominance, and there is really no question about the degree of punishment America could inflict on Iran should matters deteriorate further.

Of course, maybe Tehran doesn’t care about the “great and overwhelming force” President Trump threatened last June. Tehran claims that its “strategic patience” is not a sign of fear. “We are the nation of martyrdom,” Soleimani had boasted. “Come; we are ready.”

President Trump’s response: Challenge accepted.

James S. Robbins, a member of USA TODAY's Board of Contributors and author of "Erasing America: Losing Our Future by Destroying Our Past," has taught at the National Defense University and the Marine Corps University and served as a special assistant in the office of the secretary of Defense in the George W. Bush administration. Follow him on Twitter: @James_Robbins