This is the song yopu're thinking of:

BALLAD OF WILLIAM WORTHY
(Phil Ochs)

Well, it's of a bold reporter a story I will tell
He went down to the Cuban land, the nearest place to hell
He'd been there many times before, but now the law does say
The only way to Cuba is with the CIA

     CHORUS:
     William Worthy isn't worthy to enter our door
     Went down to Cuba, he's not American anymore
     But somehow it is strange to hear the State Department say
     You are living in the free world, in the free world you must stay

Five thousand dollars or a five year sentence may well be
For a man who had the nerve to think that travelin' is free
Oh why'd he waste his time to see a dictator's reign
When he could have seen democracy by travelin' on to Spain?

CH.

So, come all you good travelers and fellow-travelers, too
Yes, and travel all around the world, see every country through
I'd surely like to come along and see what may be new
But my passport's disappearing as I sing these words to you

Well, there really is no need to travel to these evil lands
Yes, and though the list grows larger you must try to understand
Try hard not to worry if someday you should hear
That the whole world is off limits, visit Disneyland this year

CH.

Recorded on "All The News That's Fit to Sing"
Elektra EKL-269

Unfortunately, the only practical reason the sanctions are being maintained is that it ensures the "Cuban Exile" Vote to Republican Cold Warriors in various political offices, local, State and Federal.

Best, Greg.