But Tamerlan Tsarnaev had a way out.
His great-aunt, Patimat Suleimanova, paced around the courtyard of her apartment building last week, angry and frustrated that the questions kept coming and no one seemed to be listening to her answers.
"I told you," she said, "these guys are so nice, so good. America gave them shelter. America gave them education. America gave them the possibilities to make their careers.
"Why would they be so ungrateful to America and blow up people? Where is the logic? Explain it to me."
She tried to march off, a slight woman, wearing a long dress, her hair covered by a scarf, but she could not go until the Americans listened.
"The children grew up creators, not destroyers. They had everything in life. They didn't have to die. They led a wonderful life there. So did the parents. That country accepted them and now they are called terrorists and the parents are covered with dirt."
There was no explaining it, she said, so it could not be true.
"They blow us up here a lot," she said, "and no one tells the whole world about it. Why is it so interesting when they blow something up in America?"
Makhachkala is a haphazard city of 800,000. Cars dodge each other wildly at busy intersections, free of interference from police, while officers wearing camouflage and bulletproof vests and carrying submachine guns set up road blocks on the outskirts, searching random motorists, looking for terrorists.
The day of the Boston bombings, the deputy head of Dagestan's forestry agency was shot dead outside his office. For two days before that, the village of Gimry, home to 5,000 people, was overrun by masked commandos battling militants. Residents fled, without food or shelter for more than two days, while the battle waged from armored vehicles and helicopters. Four militants were killed.
About one policeman is killed every week in Dagestan, which has about three million people. Moderate Sufi imams - who represent the traditional Islam of Dagestan - are frequent targets.
Suleimanova said Tamerlan did nothing more sinister when he was in Dagestan than visit relatives and talk. He has many relatives in nearby Chechnya, his father's homeland, and many in Dagestan, where his mother grew up.
"We talked about everything," she said. "Life, religion. For us it was interesting that he adopted Islam in America. 'Is it allowed?' we asked. 'Forbidden?' "
If something changed Tamerlan, said Habib Magomedov, a member of the Dagestan government antiterrorism committee, surely it happened in America. "I can only say that whatever happened in Boston had nothing to do with Dagestan."
As for the accusations against Tamerlan - they defy understanding.
"He had a good life," Magomedov said, "where he could have coffee and chocolate for breakfast."