CNN reports that revenge served as the motive behind the bombings at the Boston Marathon. According to CNN, Dzhokhar Tsarnaev scribbled a note asserting that claim while pinned down by police inside a boat. Tsarnaev reiterated his assertions in subsequent interviews with police after his capture.
Tsarnaev said that he and his now dead brother sought payback for the deaths caused by the military interventions in Muslim lands. He sees an attack on one Muslim as an attack on all. (I guess this does not include savage attacks on Muslims by fellow Muslims.)
Interestingly, this revelation comes a couple of weeks after Weather Underground member and domestic terrorist William Ayers denied any resemblance between the actions of his cohorts and those of the Tsarnaev brothers.
"To conflate a group of fundamentalist people who are nihilistic in some way with a group of people who spend their lives trying to oppose the murder of 6,000 people a week . . . and still the killing went on. What would you have done?"
He tries to contrast the Weather Underground's idealism with the Tsarnaev's nihilism.
Now that the surviving Tsarnaev brother has explained his motive, the distinction Ayers draws seems more blurred. Tsarnaev's motive appears just as idealistic as that of Ayers.
They both strike back at the United States on behalf of people they perceive as its victims and, perhaps more explicitly in Ayers case, change government policy.
If Ayers can convince himself, I guess that's all that matters.