The world, in all its tangled webs, will be read into the Boston bombing suspects. For some, the Tsarnaev brothers are Chechen avengers, young men seared by the long war in Russia's ''southern backyard''. For Vladimir Putin and his regime, this deed of terror in an American city is, doubtless, a vindication of the iron fist with which the Russians fought their long war against Chechnya, proof of the malignancy of the Islamist menace.
Foes of immigration can be expected to offer the Tsarnaev brothers as evidence that a nation that throws its gates wide open courts this kind of calamity. One way or the other, the matter of Islamist radicalism hovers over this episode.
There are other testimonies that speak to the puzzlement of our time, to the difficulty of drawing hard lines between cultures in conflict.