Conversation so far:
what was Peter Hitchens' contribution to journalism?
Peter Hitchens reported on the decline and collapse of communist regimes in several Warsaw Pact countries, which culminated in a stint as Moscow correspondent and reporting on life there.
what was Peter Hitchens' role in the Daily Express?
Peter Hitchens worked as a reporter of education, industrial and labour affairs, then as a political reporter, and subsequently as deputy political editor for the Daily Express.

Question: when and why did he stop being a journalist?
Self-contained rewrite: when and why did Peter Hitchens stop being a journalist?