I think as a rule of thumb government money will always flow in the direction where self interests of politicians and government servants are better served. Bu

I think as a rule of thumb government money will always flow in the direction where self interests of politicians and government servants are better served. Building a road is a time tested government program. It is mature, there is lots of competition and opportunity for publicity or kickbacks is limited. The profit margins of the road construction companies are pretty thin too. I dont think politicians benefit by building a road or bridge. Today they benefit by having outrageous programs like high speed train that will not see light of the day for decades to come (or probably never) or transmitting American programs into Cuba (which the cubans cant hear because the signal is blocked). The only way is to put a hard constitutional limit on the government spending as a % of GDP. The government is then forced to take measure to increase GDP if they want to subsidize education of Chinese prostitutes or spend $$$ on study effects of LSD on monkeys.