In 2003 all 53 Liberal Democrat MPs voted against the Iraq War. You can see Charles Kennedy's speech to the House of Commons here .
8 Jul 2016
https://www.youtube.com/watch?v=PoFVdes7qM8. Note the barracking and insults in the Commons from those gung-ho for "Blair's private war" - "unnecessary, diasterous and potentially illegal" according to one newspaper.