Visa processing delays after US computer crash

The majority of Irish citizens travel to the US on holidays and require only an electronic travel authorisation or ESTA which is not affected by the breakdown but others are awaiting student, work, business and other temporary visas which may not reach them in time for their flights.
Some residents of Ireland who are not Irish citizens also require visas to travel and may be similarly affected, while US citizens living here who need passports may also experience delays. The issuing of immigrant visas is a separate process and is not affected.