Why do people keep saying "communism" is the real reason why americans cant go to cuba?

China is not a full communist state , they relaxed mostly everything but recently are becoming even more communist then before , such as restricting the Internet and having the state own stores , these items were relaxed before anyway to answer you , its not that Cuba is communist its the fact that Cuba has been an enemy to America since the cold war , to go there is like you are spitting in the face of America