For 30 years, Jon was in the forefront of the antiwar movement since he spearheaded a group to oppose President George H.W. Bush's war against Iraq. Jon was a rare voice of reason and grace in conservative circles, patiently pointing out how foreign warring was destroying American freedom – as well as wreaking pointless havoc abroad. He was also a generous supporter of groups ranging from the Future of Freedom Foundation to Antiwar.com, where his columns trounced bloodthirsty politicians of all stripes.
Jon consistently raised issues that other Washington activists would not touch. In a 2005 Antiwar.com column headlined "Torture, the GOP, and the Religious Right," Jon wrote: "The idea that America is 'good' and therefore need not show a decent respect to the opinions of mankind runs very deep among those now ruling Washington."