Last week the United Kingdom's National Archives released previously classified government papers under the "30-year rule." This is a law in the UK that allows cabinet papers to be released publicly 30 years after they were created.Amongst the papers are many documents about the US invasion of Grenada in 1983, including letters between Margaret Thatcher and Ronald Reagan, as well as much correspondence between Caribbean leaders at the time and the British Foreign Office.
In the US-UK letters is the Thatcher government's position against military intervention in Grenada. This is stated most overtly in a "Dear Ron" letter the day before the invasion from Thatcher, whose Foreign Minister Sir Geoffrey Howe, had told the House of Commons the same day there was "no reason to think that military intervention is likely to take place."
Regan's 23:00-hour reply (not returned as Dear Maggie, but Dear Margaret, for those interested) was unequivocal: the invasion would happen the next day, and there was nothing Thatcher or the British could say."We are already at zero," Reagan told a blindsided Thatcher.