I think the lack of transport in a city like Milwaukee is more based on growth rate than actual money issues. Milwaukee is an "old" town. It has relatively stagnant growth. Therefore, the ability and will to plan for future population increase is lessened. In contrast, many of the southern "boom towns" that have double digit growth in the 90's and 2000's have created ground up transit systems including light rail. Many of these didn't work well (hello Atlanta) because urban planning foresight has been generally pitiful in the south. However, the point being that in order to cross the hump from a large enough city without an option to one that invests in new transport infrastructure is usually a prospect for future or a recent past trend of fast growth. If MKE grows again (unlikely based on US population shifts), then public will for rail transit and the like will increase. Until then, it's likely you are stuck with what you have.