If you're the child of an immigrant, like me, or perhaps an immigrant yourself brought here as a child, you know what it's like to have one foot planted in the old world and the other planted in the new, in this amazing, sometimes frighteningly free American culture.
Some of you know what it's like to be lost, at least for a time, desperate for America, desperate for acceptance, hoping to become part of this place, and still find comfort by idealizing the old ways that you know mostly from stories around the dinner table.
At first, immigrant families might not feel completely American here, but when they go overseas or across the border to the land of their ancestors, what is the first thing they're called?
And what of those who fail to assimilate into our American culture and begin drifting, desperate to blame someone other than themselves? They're susceptible, they're hungry to belong to something, they're ripe for suggestion, and this yearning makes them useful to evil men.
"It's an issue for immigrants," said terrorist expert Anne Speckhard. "They basically have two selves — the part that belongs to the old country and the part that belongs here."
Speckhard is a professor of psychiatry at Georgetown University Medical School who lectures law enforcement and counterterrorist experts and works with NATO, studying post-traumatic stress disorder and factors that lead to the recruitment of terrorists.
She's the author of "Talking to Terrorists: Understanding the Psycho-Social Motivations of Militant Jihadi Terrorists, Mass Hostage Takers, Suicide Bombers & 'Martyrs,'" for which she completed more than 400 interviews of terrorists, their families and friends, and even stayed in some of their homes.
She's made the study of the terrorist mind a large part of her life's work, and I wanted to know more about how young people raised in free societies become susceptible to recruitment and radicalization.
Like many of us, she's been fascinated by the Tsarnaevs, particularly since she worked with second-generation Muslim immigrants in Europe and tracked their problems assimilating.
"In Europe, you will find much more of a vulnerability to the militant jihad, because in some ways, they're blocked from mainstreaming," she said.
"Here, I wouldn't expect to see that. One thing we did see in Tamerlan's case, which I would expect to see, is if you get a kid who came out of a very conservative Islamic culture, starts partying and doing drugs here in the West … he's at risk to end up what's often referred to as 'reverts,' people who go back to the faith.
"It's almost like they're looking for their identity in converting to a conservative form of Islam," she said. "It's so sad to think of any young kid getting sucked into that, but that's how these (terrorist) groups and these ideologies operate. They prey upon their anxieties and vulnerabilities."
Martyrdom, she said, sometimes becomes an option for aimless young people lost in the West. It's clear that Tamerlan had become lost for a time. His boxing career fell apart, there were drugs and loud parties, and then the conversion to radical Islam and ultimately, authorities say, to terrorism.
Please understand that I'm not saying that young immigrants or the children of immigrants make terrorists. I'm a child of immigrants. And I'm not making excuses for the Tsarnaevs. They were welcomed here; America fed and housed them at taxpayer expense, and they repaid our hospitality with murder and horror. I don't pity them, but I do want to understand what made them.
Relying on simple characterizations won't do. Blaming prayer and religion might offer politically expedient answers, but it doesn't illuminate a deadly dangerous problem that we'll have to deal with, here and in Europe, for years to come.
For an immigrants to truly become American, they have to buy into the culture. When I was a child, my father the Greek immigrant reinforced the wonderful freedoms he found here. He and my mother stressed English in the house. They insisted that we respect family, cultural and religious traditions, but also that we embrace this country and assimilate.
So we played the American sports of baseball, football, and we played them desperately, for the love of the games, yes, but also to win acceptance, hoping to become part of this new tribe, and become Americans.
And the others who become lost in this new land? They're susceptible. In some cases, Islamic martyrdom offers an out, particularly for those who think they may redeem and purge themselves through violence.
Speckhard told of a young man she interviewed years ago.
"I met a young man of Kashmiri extraction in Britain who told me he wanted to die as a martyr and said he wasn't going to attack in the UK. He had UK citizenship," she said.
"But he would definitely end his life fighting a 'jihad.' When we went on and on, I finally said, 'Do you have some terrible sin in your background that you're really worried about?'"
"He said yes."
Speckhard said that the problem is growing in the eurozone, which has a large Muslim population and is imploding economically, sparking the rise of ethnic nationalism.
"It's usually the immigrants who lose their jobs first or don't become employed," she said. "And the European countries have this large Muslim diaspora. It's going to be interesting to see how this plays out."