It would be inaccurate to portray Ireland's position during WWII as 'supporting Hitler'. If anything, the Irish position was supportive of the Allies.
Allied aircraft were authorised to overfly Irish airspace, all be it in a restricted way. Allied air crew who were forced to land in Ireland were 'assisted' to the border with Northern Ireland. There were a number of Luftwaffe bombing raids on towns and cities in Ireland, including the raid of the night of 31st May 1941 against Dublin, known as the North Strand bombings, which claimed the lives of over 30 civilians and injured nearly 100 more. It is suggested that the raid was in retaliation for fire tenders from Dublin, Dundalk and Drogheda assisting the fire service of Belfast (in Northern Ireland) and surrounding areas following the "Belfast Blitz" of April '41.
The Irish government protested to the Nazi's over both the Belfast and Dublin raids.
JAS