Most days you can't see the jet exhaust but some days it covers the entire sky with a white haze and other days it looks like a gigantic tic-tac-toe game in the sky. Experts tell us it's all water vapor but artificially generated water vapor in the sky is unnatural and the gigantic fossil fuel burning engines consume a hell of a lot of relatively dirty fuel over our heads. My guess is that it ain't all water vapor we see. The elites depend on air travel so they don't want to kill the golden goose so I doubt if jet engine exhaust will be the subject of much controversy.