McKay wasn't supposed to be in the fight. The state department wanted no US fingerprints on the operation and plausible Deniability was the purpose behind using five commando boat crews if a mercenary were killed in the Congo So be it but if an American turned up shot and dead there particularly an ex-navy personnel It would be much more difficult to ignore and whitewashed away. Ultimately, McKay was the only one who unexpectedly ended up engaged in combat so they're doing this big amphibious operation  and again get the book for really cool details about it.