As tensions flare abroad, elected leaders in the United States want to be seen as doing something. In the days since Soleimani’s death, other major cities have also promised greater vigilance, more police on the streets, and closer cooperation with state and federal authorities based on vague intelligence that tells us simply that Iran is angry. In the years after 9/11, Republicans capitalized politically on the public’s fears, and Democrats ever since have been eager to show commanding leadership. And for Democratic mayors with higher political ambitions—a category that briefly included de Blasio, who made a short-lived presidential bid—the orderly patrolling of a homeland under siege might make a perfect narrative foil to Donald Trump’s impulsive decision making.
Read: Is American any safer?
Accepting risk is a profound challenge for American homeland-security planning. Military planners must make assumptions about acceptable losses. In the civilian context, we have no such concept, meaning that officials are expected to act on any potential for harm, however vague or indirect. You can tell me that the threat of an attack has increased 1 percent, and as a rational person I would view that as negligible—unless you tell me that my child is among those facing a 1-percent-greater risk, in which case you had better do something. Because American officials and the public they serve have no easy way of discussing the differences among different levels of risk, we see any visible sign of action by police and other agencies as progress. But sometimes action is mere entropy.
Americans can be pretty confident that Iran will respond to the attack on Soleimani, but how, when, and in what form elude prediction. The response could happen in Iraq against American troops or elsewhere in the Middle East against U.S. interests—or the interests of American allies such as Israel or Jordan. The target could be a military base, an embassy, a shipping route, or an oil field. It could happen today or months from now. It could be launched by Iranian forces or proxies in the area. The operation could involve assassins, or drones, or missiles, or cyberattacks. The sheer volume of chatter and the multiplicity of leads produce what’s known in the homeland-security world as intelligence soup.
Nearly 20 years after 9/11, American elected officials of many political stripes remain wedded to the idea that threats of terrorism or hostile military action by foreign actors can be regulated at will, as with an on-off switch.
Under the multi-hued terrorism-alert system devised by the George W. Bush administration, the federal government sought to notify first responders and the public of potential shifts by shifting from one color to the next—for instance, from yellow (elevated risk) to orange (high risk). These shifts were based on intelligence, much of it undisclosed, that was publicly presented as credible but not specific. In practice, the system was subject to abuse and mere whim. Cities would try to raise their level of readiness, often redeploying their employees and spending more money, without any clear sense of which threat they might be preparing for.