>>13105288While Don't think I'd call urban planning a science, in the same way I wouldn't call economics a science, I do think it's pretty neat.
Having lived in Tokyo for a while, which is really more like a 5 minute city depending on the district, I do think that it's probably possible in north america but I don't think it's something you really plan for.
The biggest factor in my opinion as to why japan works really well in this regard is that their zoning laws are a lot more sensical and more hands off than they are in the US, in that everything is sort of graded on a nuisance level, and everything below a certain level is allowed in a given zone, IE there's no restrictions on building residential in a commercial area. see picrel.
In the US, with Euclidian zoning, everything has to be mapped out explicitly, and considering there aren't any omniscient city planners I know of no city ever does this perfectly.
In japan, basically everything is in some way mixed us zoning, which means that if there's ever a need for any service or commercial function in a residential area, the market will just build it. This also has very good effects for making housing affordable, since there isn't nearly as much land that's dedicated solely to single family housing.
of course, Tokyo having an extremely useful public transit system helps alot as well, but even just walking you're still generally able to get anything you would need on a day to day basis.