That's pretty much true, and not unreasonable grounds for emotion. Chevy is a legitimately iconic brand. I myself have been brought near to tears by products with a lesser claim to my heartstrings (I refer especially to the Kitchen Aid dishwasher, which had me all but sobbing back in the late 80s to the tune of "Through the Years.")
The question is, though, if a consumer product can credibly claim to be a part of the American Experience, does that entitle it to invoke other aspects of the American Experience that matter a lot more than a pickup truck? Such as Rosa Parks on the bus, such as Nixon's resignation, such as Vietnam, Martin Luther King Jr. and Ground Zero?
Can it say "This is America, warts and all, and we're a part of it, too?"
I have three answer:
1) Of course they can; it's (still, barely) a free country.
2) Why not? The ad from Campbell-Ewald does nothing more than place an iconic brand in the great tapestry that is our cultural history.
3) No. NO!
In the end, no matter how deserving is Chevy's claim to being a fixture in American life, to juxtapose it against these searing moments of our history is to cheapen them. Bad enough that George Washington founded the republic and Abraham Lincoln saved it only to be posthumous shills for Presidents Day sales.
Can't we at least be respectful of modern history, the scars of which we still see, the pain of which we still feel?