I think it should be because diplomats is the representative of a nation and negotiating with other nations could be more easier if we're already friendly with the diplomat. Also the way we treat their diplomat is also the way of how we treat the nation he/she representing and it would add a good standing in the global status if we are respecting the diplomats.
Answer:
The Johnson administration planned for major American military action against North Vietnam nearly five months before the 1964 Tonkin Gulf incident, according to secret government documents made public yesterday by the New York Times.Jun 14, 1971
