I've always read Lolita as being about growing Old World impotence-- both cultural and political-- in the face of rising American power in post WWII global society. I've understood it to be a dark comedy in that sense, and I thought that was what Nabokov was going for too. I mean, as a metaphor, it's still a very provocative one, a man seducing a child, but I've never seen Humbert as anything other than a pan-European aristocrat, and the mother and daughter as pre and post WWII America.
Oh absolutely and I think the “road trip” across America definitely belies that interpretation. Humbert is a self-important, self-absorbed, snobby Old World European man and Delores represents everything that’s both terrible and enticing about post WWII America: her love of movie stars, fan magazines, disposable off-the-rack fashion, sweets, and trivial pursuits like tennis.