"He drew a picture of our house burning down and he'll tell anybody that he's going to burn our house down with us in it," she told The Associated Press in a telephone interview. "It got to be where you feared for your safety. It was terrible."
One of the three elements of the "MacDonald triad" is setting fires, the other two being cruelty to animals and bed-wetting. The triad has been found to be correlated to the emergence of serial killers. Serial killers are psychopaths -- though not all psychopaths are serial killers. It's possible that the adoptive mother found that her son showed signs of being a psychopath, and was not too happy about it.
Qualities that make psychopaths what they are include pathological lying, lack of empathy, amoral behavior, and a superficial sense of charm, the latter making them less likely to be identified and hence even more dangerous to others.
Research performed by the group of Essi Viding at the London Institute of Psychiatry found that both "callous-unemotional traits" and "antisocial behavior" in children, which are "early warning signs of life-long psychopathy," were "under extremely strong genetic influence and no influence of shared environment." This confirms what many others, notably parents of psychopathic children, have noticed, namely that psychopaths are born and not made.
Viding found that a subset of children with antisocial behavior but low levels of callous-unemotional traits did have some influence from shared environment. One might imagine that a Russian orphanage might not be the most caring of places and that it could influence the development of antisocial behavior.
So, one can speculate that the American woman who adopted that Russian boy found that she had a load of trouble on her hands, perhaps a psychopath. Whether or not her actions were moral, probably no amount of parenting on her part would have had much influence on the boy's behavior, for he was either born that way or had already grown up in an environment that permanently shaped his mind.
In his book The Blank Slate, Steven Pinker theorized that psychopaths and other "born criminals" represent the extremes of a spectrum of personality traits that everyone has, and that these are largely heritable. The lesson there is that psychopaths and other violent or manipulative people will always be with us, that parenting will be of little help in the prevention of psychopathy, and that, other than being aware of their presence and ensuring that violent criminals remain in prison, there's little we can do about it.