You&#x27;d have to construct a model where you guess the impact of the taxes vs. the impact of potential investment of the same money otherwise. I suspect this is harder than it looks because it isn&#x27;t discussed much ( although it could be that people simply repeat their ideology rather than trying to make it empirical ).<p>Not all bridges and roads are equally valuable. And in some areas, the dominant method of financing new roads is through tolls. I once estimated the number of man-years per day lost to congestion on I75 in Dallas around 1985 . It was quite the figure.