In order:
Public land will be permanently dedicated to rails and stations and things, if you want to cover the same area with transit access, you'll need similar, if not the same public land.
Parking minimums are not about being pro-car so much as being about anti-poor. This is a subsidy to entrenched interests, not to cars.
Police make money from traffic enforcement. Many departments get their whole budget from that. Many towns get their whole budget, above and beyond the PD, from it. Eliminate cars tomorrow and you bankrupt a huge percentage of non-major cities and all small towns.
Wars of aggression over oil are likely over due to fracking and oil sands, but I'll grant that they were bad while they were happening. Now, how are your predominantly diesel trains going to be powered without oil?
Oil subsidies are a problem. I would love to see congestion pricing and an end to all subsidies for transit, trains, buses, cars, bikes and pedestrian behaviors. We do not and never will again live in that world.
Deaths due to automobiles are at a record low per passenger mile and continuing to fall. Every time we make roads and cars and esp new cars more expensive, these rise as people limp their dangerous old clunker along a bit more. Weirdly, the requirements for safety technology cause people to drive older, less fuel efficient cars and the requirements for better emissions cause people to drive older, less safe cars all due to rising prices. Perhaps we should subsidize the removal of old cars (cash for clunkers)?
I don't think you can blame sedentary lifestyles on driving. That's a step too far -- it's a factor, but it's by no means the biggest or the most consistent. I doubt that we'd be able to attribute anywhere near enough health problem to only and specifically long commutes to even really price this externality.