What was the Motivation for the Tsarnaev Brothers?

For John, BLUF:  There is a lot more to learn about the Boston Marathon Bombing.  Nothing to see here; just move along.

Here is a quote from an article in The Wall Street Journal, by By Pervaiz Shallwani, "Details Emerge of Alleged Carjacking by Bomber Suspects".

The victim told police he was driven to a Shell Gas Station on Memorial Drive in Watertown. Inside the car, the brothers "declared to [the victim] that they were the Boston Marathon bombers and would not kill him because he wasn't American," the report said.

To me this suggests that the Tsarnaev brothers were working out some hatred of Americans.  Does it exclude the possibility they were doing something in support of al Qaeda or al Qaeda like organizations?&nbps; No, but it says we need to gather the facts before we render final judgment.

From the Federal US Code, Title 18 › Part I › Chapter 113B › § 2331:

(5) the term “domestic terrorism” means activities that—
     (A) involve acts dangerous to human life that are a violation of the criminal laws of the United States or of any State;
     (B) appear to be intended—
          (i) to intimidate or coerce a civilian population;
          (ii) to influence the policy of a government by intimidation or coercion; or
          (iii) to affect the conduct of a government by mass destruction, assassination, or kidnapping; and
     (C) occur primarily within the territorial jurisdiction of the United States.

While the Boston Marathon bombing seems like "domestic terrorism", who were the Tsarnaev brothers trying to intimidate or coerce, or what policy were they trying to influence or what conduct were they trying to affect?  There is more to learn.

Hat tip to Ann Althouse.

Regards  —  Cliff