What is the REAL purpose of Russia's ban on American adoptions?

MOSCOW (AP) – Thousands of people marched through Moscow on Sunday to protest Russia’s new law banning Americans from adopting Russian children, a far bigger number than expected in a sign that outrage over the ban has breathed some life into the dispirited anti-Kremlin opposition movement.

…Russia’s adoption ban was retaliation for a new U.S. law targeting Russians accused of human rights abuses. It also addresses long-brewing resentment in Russia over the 60,000 Russian children who have been adopted by Americans in the past two decades, 19 of whom have died.

…Protests against the adoption ban were held Sunday in a number of other Russian cities, but in most places only a few dozen people took part. In St. Petersburg, about 1,000 people turned out to show their opposition to the law and to Putin. Some held up a poster that read “Don’t play politics using children.”