I don't know whether he has any passionately held views. There must be more to him than a pastiche of an Englishman. I remember when the Americans went into Afghanistan and Boris said, "Wouldn't it be funny if - yeah - the Americans took a hiding." He's not anti-American, but he's mercurial. It would have been a better story.
Stuart Reid, quoted in "Boris: The Rise of Boris Johnson" by Andrew Gimson.