Also, immoral/unjustified != illegal.
Also, immoral/unjustified != illegal.
And while the treatment of Cuba is indeed appalling, or at least incongruous in relation to, say, Saudi Arabia, there are rather meaningful differences between the parties.
Thawing relations with Cuba was among Obama's signature achievements. This included the reopening of Embassies, allowing travel, and vastly increasing legal avenues for trade and investment.
Some (but not all) of this has been delayed or cut back under the current administration. At the same time, Saudi Arabia enjoys unprecedented support and access at a time where they are more hostile in Yemen, Qatar, and The Streisand Lobby at the Istanbul Consulate.
https://www.theguardian.com/world/2018/oct/03/international-...
https://www.cnbc.com/2018/10/05/us-rejects-international-cou...
As a condition of easing sanctions, Iran filled the rector core of it's active nuclear reactor with concrete and was found to be in compliance with all the terms of the agreement. Good luck getting any other nation to enter into negotiations like that with the US in good faith again.
The Iranian regime is awful. They're appalling extremists and oppressive tyrants. No argument there, but that's on them. It doesn't justify recklessly violating treaties and unilaterally breaking agreements, and establishing a track record of doing so. If anything, demonstrating a track record of honesty and respect for straight dealing is even more important when dealing with such people.
Having said that, I do NOT condone sanctions in any form.