In the early months of 1938, as the US trade negotiations rumbled on, Chamberlain also tried to improve Anglo-Irish relations. Here too, Chamberlain was willing to offer up concessions in the hope of an improvement in atmosphere. Controversially, this included ceding control of the ‘treaty ports’ – three harbours on the western Irish coast from which naval power could be projected far out into the Atlantic, which had been retained by the British after 1921. Since, realistically, they could not have been defended against a hostile hinterland in time of war, Chamberlain thought they were better returned to Irish hands in the hope of friendship in the future. When the prime minister managed to settle the deal himself in direct talks with the Irish taoiseach, Éamon de Valera, it confirmed his faith in the power of personal negotiation.

— Britain's War: Into Battle by Daniel Todman (Britain's War, #1)