I may have missed it but I have yet to see any reference to a nuclear attack on the Carribean, Central America or the north coast of South America in any of the GDW sourcebooks.
If the Panama Canal wasn't a nuclear target then I doubt that the French rocket launching site in French Guyana, or any local oil refinery or military base was a nuclear target either.
The Dutch forces in the Antilles are a bit on the light side. One Marine company, a frigate, a few patrol aircraft and some para-military and police. The Dutch also have their hands full in Europe with the nuclear attacks on the Netherlands and the French occupation of the Rhine. I doubt their will be any reinforcement, and Dutch forces in the Antilles will be low on spares, ammunition etc.
There is the possibility of some help from NATO allies in the region. The Americans are pre-occupied with their own problems but there is still likely to be some US forces in Panama, Puerto Rico and the US Virgin Islands. Unknown if such forces are MilGov or CivGov.
This is a non-canon variant writeup from Orrin Ladd.
http://t2k.homestead.com/southamerica.htm
Also likely some British forces in the region. British territories in the region include the British Virgin Islands, Caymen Islands, Montserrat and Turks and Caicos. Also Bermuda in the Atlantic. British had forces in Belize until the mid-1990's; RAF Harrier flight, Army helicopters and some infantry (Belize still has a British Army training base). Missile Frigate usually based in Caribbean and certainly some para-military and police forces on islands, and probably some small military forces. Most of the rest of the English speaking Caribbean is also British Commonwealth and is closer politically and culturally with Britain than it is with America, although Jamaica is likely to be a hell hole.
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