The Russians were considered the new enemy even before the last shots of World War II were fired. U.S. intelligence teams and British were right behind the troops after the landing in Normandy. B.I.O.S. and C.I.O.S. teams often competed for the same "targets." Scientists, engineers, documents, patents, aircraft, other military equipment, and entire factories were carted off. One of the main reasons being to deny them to the Russians. The Russians were the only military threat to be taken seriously at the time. And there was a concern that they would continue to advance into western Europe in spite of any agreements.
See here for a description of a British plan called Operation Unthinkable.
http://members.tripod.com/~american_almanac/church.htm
Ed