The political response to the Boston Marathon bombings suggests that we live in an age of shrink-wrapped, prepackaged opinions.

When something new comes along, we hasten to squeeze it into whatever framework we were carrying around with us a day, a month or a year before.

When the ghastly news from Boylston Street first hit, there was an immediate divide between those who were sure the attack was a form of Islamic terrorism and those just as convinced that it was organized by domestic, right-wing extremists. April 15 was Tax Day, after all.

Unless I’m missing some obscure Web site out there, absolutely no one imagined what turned out to be the case: that two young immigrants with Chechen backgrounds would be held responsible for unleashing the violence. Chechnya was not on anybody’s radar screen — and it does not appear that the conflict in that rebellious Russian republic actually had much to do with the alleged actions of Tamerlan and Dzhokhar Tsarnaev that day.

We then moved, with dispatch and without pausing for more information, to show how the event proved that our side was right in any number of ongoing debates.

Opponents of immigration reform used the fact that the brothers are immigrants as a lever to derail the rapidly forming consensus in favor of broad repairs to the system. Supporters countered, defensively, that if there is any lesson here, it’s that our approach to immigration needs to be modernized. In truth, this horrifying episode has little to do with immigration reform one way or the other.

We fell back on other familiar ground. Sen. Lindsey Graham (R-S.C.) said we should assume these brothers had to be linked with one of our international enemies and that Dzhokhar, the surviving brother, should therefore be tried by a military tribunal and not in a normal American court, the venue to which his status as a U.S. citizen entitles him.

The Obama administration doesn’t get credit for much these days, so it deserves courage points for deciding that Dzhokhar should be treated in a way that protects the rights of all other citizens.

And, of course, what I have just written means that I cannot claim to be immune from the very forces I’m describing. My own passion for saner gun laws similarly led me to ask why we have not focused more on how the bombers obtained their weapons or why it was so hard (because of the National Rifle Association’s opposition to chemical “taggants” in gunpowder) to trace where they got the material to build their bombs.

My faith in a tolerant, pluralistic America made me worry that hundreds of thousands of law-abiding Muslim citizens could become the victims of our anger — much as Italian Americans were stereotyped in the days of Sacco and Vanzetti.

I also found it disturbing that we have given scant attention to the April 17 explosion at the fertilizer plant in West, Tex., that killed 15 people and injured more than 200.

As the labor writer Mike Elk pointed out this week in a Post commentary, industrial accidents are far more common than are acts of terror. We have more control over how we enforce worker-safety laws than we do over random acts of violence. Yet we have allowed the Texas story to be buried beneath all our speculation about the Tsarnaev brothers.

Ann Telnaes animation: Senators Graham, McCain and Rep. King call for designating the surviving Boston Marathon bomb suspect as an “enemy combatant.” (Ann Telnaes/The Washington Post)

Here again, since Elk and I share a concern for labor rights, it’s not at all surprising that we’d make this argument. You might ask if my complicity in a culture of preconception should provoke a certain humility.

Well, it does.

I’d acknowledge that none of us can get through the day without making a lot of assumptions. All of us have intellectual, ideological and moral commitments that we bring to bear upon what we think about almost everything.

But the hyperpolarization of our moment has sped up the rush to (contradictory) judgments, a practice further accelerated by new technologies. We have less patience than ever with the often­painstaking task of gathering facts. We are better informed yet seem more efficient than ever in manufacturing conspiracy theories.

I mistrust moralistic nostalgia for some nonexistent golden age of reason, and I have contentedly joined the bracing new-media world. The past had problems of its own.

Still, I’d insist that “crowdsourcing” is quite different from reasoning together, an art we seem to have forgotten. And at the risk of disrupting the productivity gains of the opinion-creation industry in which I happily participate, I wish we were better at remembering three words: Stop and think.

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