Books:
* The Irish: Portrait of a People (1985)
* The Fall of the Republic (1992)
* The Irish Disease: The Failure of Politics (1996)
* The Great Irish Famine: A New History (2001)
* The Suicide of Ireland: The Celtic Tiger Turns on Itself (2004)
* The Irish Revolution: 1913-1923 (2016)
Journalism:
He has written numerous articles and columns for publications including:
* The Irish Times
* The Sunday Times
* The Daily Telegraph
* The Spectator
Television and Radio:
* He was a regular commentator on the Irish television program "The Week in Politics".
* He has also appeared on other television and radio programs in both Ireland and the UK.
Other:
* He is a founder of the Irish Institute of International Affairs.
It's worth noting that some of his views and opinions have been controversial, and he has been the subject of criticism for his views on Irish politics, the European Union, and other topics.