Potential economic liberalisation

Casual observers of US foreign policy and its economic relations with foreign countries that its has previously sanctioned/embargoed were happy to see the US was overcoming its antiquated embargo on Cuba - an policy implemented at the height of the Cold War to stymie Russian nuclear capabilities on the island 90 miles off the coast of Florida.

However, even though resuming trade relations with the US, Cuba - which has recently lost its national hero Fidel Castro - still has a number of challenges to face. The following article written by the Harvard Business Review details the difficulty the island could face in attracting enough capital investment, as well as kickstarting a stagnant state-run economy, which has meant that both people and companies have relied on government subsidies.

Cuba may not be as advanced economically speaking as Iran - whose sanctions have recently been lifted by the UN at the beginning of the year - it is safe to say that the lack of trade with the US has weakened both (and to some extent has shaped their economies). I wonder where the similarities between Cuba and Iran in overcoming obstacles to revamp their trade begin and end?