No, but he is part of the Kagan Clan: Robert and his brother Fred Kagan. Robert's wife Victoria Nuland and Fred's wife Kimberly Kagan.
Victoria Nuland had worked VP Cheney and she was hired into the State Dept to oversee Libya and became best known for the Benghazi talking points memo. Later she was put in charge of Ukraine.
Kimberly Kagan had started the Institute for the Study of War. Elizabeth O'Bagy worked for Kim Kagan and was very influential in shifting opinion on intervening in Syria. O'Bagy escorted John McCain on his trip to Syria to meet with the "good rebels".
Behind the scenes, the Kagans are very influential on foreign policy.
Robert and Fred are sons of Donald Kagan, professor of history at Yale and author of many books on Greek history. Donald was born in Lithuania but I doubt concern for Lithuania is the starting point of their foreign policy views.