He funneled cash and weapons to the Irish Republican Army from Libya, and was involved in bombings that targeted Margaret Thatcher and others, killing scores of people.
A writer, editor and political adviser, he broke with the left over its criticism of Israel and what he saw as its anti-Americanism. But he also became a critic of Donald Trump.
The writer and editor Sol Stern at his Manhattan apartment in 2008. A liberal turned conservative, he was known for his largely nonideological judgment and his willingness to change his mind.