In this image from video provided by Ryan Hoyme, the second explosion can… (Ryan Hoyme )
Suddenly, everything looked like a bomb.
"Please note," one Boston first responder warned his colleagues Monday, in the churning radio traffic that immediately followed the bombings at the Boston Marathon. "There’s three handbags in front of the bleachers, in front of the truck -- you might want to get away from those bags."
The two blasts that killed three and wounded scores more was, in many ways, a specific type of fear finally realized: In the days, months and years after Sept. 11, 2001, attacks, officials cautioned Americans to be on the lookout for terrorists going after so-called soft targets such as cafes and malls, where people congregated.
After the Boston blasts, the authorities tiptoed around publicly labeling the explosions an act of terror. Behind the scenes, officials said the incident was "clearly an act of terror," as one official put it -- but, again, without a sense of who might have been behind it.
Right after the blast Monday, scanner audio revealed officials wading into a scene of pandemonium, where every abandoned bag could be perceived as a life-ending threat.
"I want all the SWAT teams to go back to the base right now, get their rifles, get their gear, and get back down here," one unidentified official radioed.
Another shouted about "secondary devices," which is cop and soldier talk for bombs placed alongside other bombs, intended to kill those rushing in to help, like the officers themselves.
There was a suspicious backpack, "a suspect package beneath the bleachers in front of the library," “some form of a possible device that has not detonated," and yet another "possible device." Or maybe it was just a belonging dropped by an onlooker in panic.
The kind of well-known post-bomb anxiety known all across Baghdad -- which saw its own coordinated attacks Monday, killing 50 -- had suddenly swept into Boston.
As Esquire's Charles Pierce wandered the scene in Boston, shooed around by cops fearing for everybody's safety, he noted, "The very worst two words in the English language in Boston, where the latest reports say at least two have been killed and dozens have been injured, this afternoon were these: 'secondary device.' ... On a day like this, everybody’s nervous. Everybody’s scared. Nobody knows anything. And everything is a secondary device."
Northeastern University criminologist James Alan Fox was only a block away from the blasts when they occurred, and he happens to be something of an expert about this sort of thing.
Just not so much about this specific thing.
"We don’t know a lot, do we?" Fox told the Los Angeles Times in a telephone interview. "We don’t know if this is an organized group or some amateurs. No one has taken credit yet, which might suggest the latter. But we don’t know," he said, then quickly adding, "and hopefully we will."
The attack came on the same week as a number of dark and notorious anniversaries: The 2007 mass shooting at Virginia Tech, the ending of the 1993 Waco siege, the 1995 Oklahoma City bombing, the 1999 Columbine High School shooting, to name a few, plus the more abstract -- Hitler's birthday on April 20, and, of course, tax day on Monday.
Less ominously in terms of anniversaries, though, Monday was Boston's day, or "Patriot's Day," as it's called, where the city bursts to life with a Red Sox home game and a world-renowned marathon.
"This is the day Boston shines in the spotlight," Fox said, "and that puts this event in the spotlight. If it happened in another day, sure, it would have had an impact, but not quite the same. This will be remembered every Patriot's Day."
The attack itself puzzled him and had him pondering the comparisons.
"In the past, we’ve been caught off-guard, literally sometimes, by terrorist attacks that have occurred on ordinary weekdays when people are going to work," Fox said. "We weren’t particularly alert [in those attacks], we didn’t have any high-level security, everything was normal -- until it wasn’t.
"And that was to their [the attackers'] advantage, whether it be Oklahoma City or 9/11, or even something like [the Unabomber] Theodore Kaczynski, they always took advantage of the fact that we weren’t expecting them."
The strongest comparison Fox could think of was the 1996 bombing of the Olympics in Atlanta, which left two dead and more than 100 injured.
The mastermind in that attack was Eric Rudolph, an antiabortion fringe figure who would later go on to bomb an abortion clinic and a lesbian nightclub and run from the authorities for five years in North Carolina. At his sentencing in 2005, he said he bombed the Olympics in the hopes that the Games would be canceled and "to confound, anger and embarrass the Washington government in the eyes of the world for its abominable sanctioning of abortion on demand."
The attacks Monday came with no such message or manifesto -- just fear, and blood, and tears, and the inevitable searching for some kind of meaning behind the chaos.
"We had security, and a good deal of it," said Fox. "Sometimes, a bomber just wants to feel powerful, and create havoc and chaos and confusion, and clearly that’s what happened here."
In Boston, as of late Monday evening, little else was clearer.
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