While Ireland has an arrangement in place with Australia for mutual exchange of driving licences, this agreement does not cover licences which were originally obtained as a result of exchange arrangements with third parties. When bilateral agreements on exchange of driving licences are reached with other jurisdictions, they are preceded by detailed examination of the two licensing systems in both jurisdictions by the respective licensing authorities. The purpose of this is to ensure that the two regimes are compatible.
The reason for such detail is to ensure that, when we arrive at an agreement, the people who will obtain licences as a result will have met standards to obtain a licence which are comparable to our own. We cannot vouch for the standards involved in obtaining third party licences, unless the third party country is one with which we also have exchange arrangements. As we do not have an exchange arrangement with the USA, we cannot exchange an Australian licence where it was granted in exchange for a US licence.