My guess is Reagan, like many in the US, neither read nor understood Marx or Lenin. Also, reading and understanding their work doesn't indicate agreement, so the statement is false and inflammatory. Lest MR forum readers assume all Americans are wilfully ignorant about history, Marx and Lenin were required reading when I went to university in Virginia, along with the great works of many other philosophers and social scientists across the political spectrum. Then again, that was before the Unenlightenment.
Anyway, we're diverging from the thread so I have said my piece.