Can a US citizen travel to Cuba if they connect planes outside the US?

Yes, you are able to fly from US to Cuba if you connect outside of the US before entering Cuba. I went last year and we connected through Cancun. You cna also connect throuh Mexico City. You are not able to book a flight directly from US to Cuba. You will have to but a ticket from a US city to Mexico and then buy another one from Mexico to Cuba. From what I understand it is not illegal for a US citizen to go to Cuba, but what is illegal is to spend money in the country. If you are caught by immigration when coming back into the US and they suspect you may have gone to Cuba, they can search your stuff and if they find anything you are subject to thousands of dollars of fines. I'm pretty sure there are notices in the airports in Mexico like Cancun where flights usually connect from letting you know the law. Just check out the US department of foreign affairs or travel to make sure you aren't going to break the law.