Not from the US, but I lived there shortly and was asked to move there and had to decline. To me it's pretty clear that your single biggest problem is your suburbs and car culture. Everything from anti-social behavior, social anxiety snd isolation, depression, obesity, diabetis, divorce, as well as partisan politics stems from it. Subsidizing that mess should be the last thing you should do.

Other countries subsidize rural areas primarily for 3 reasons: 1. Certain political parties have their base in rural areas and want to subsidize their life style. 2. Strategie for making the country more food-independant through farming. 3. Military strategie for having people in remote areas.

Nobody in the world subsidizes non-productive suburban sprawl.