Interesting that he brought it up now - when kinda the same thing is happening in his life (except it's him and OW who threw the firebomb - but MLCers often don't know quite how they ended up where they did).
You might bring it up to him - gently - by saying "Gee, H, I was thinking about what you told me yesterday about being firebombed. I was wondering if it feels a little like that to you now, with all the changes coming in our lives?"