promoted to commander on 31 december 1958, he undertook further study in the uk and usa. as a 'war planner' he worked in the supreme allied commander atlantic (saclant) in the us. it was his time in the us, working on a multi-national staff, that opened mccgwire's eyes to what one can achieve when unconstrained by deeply ingrained service deference and loyalties. at that point he realised that he wanted to join an international organisation such as the un.