We got to where we are, in the U.S., because we've got massive inefficiency in state and local government. There's only a handful of cities that are massive enough to do projects that would require hiring highly paid specialists to manage these huge projects. Similarly, most states have very few opportunities for long-term career-building public project management. (There's like 3 west of the Mississippi.)
But consolidating all of this expertise in a federal agency tasked with planning and executing massive public projects would allow us to hire career-oriented planners and keep them busy for ever. It's how we run the military, of course. And, ironically, the military is a leech on the U.S. taxpayer, massively bloated and throwing money at foreign problems in the most ham-fisted way just to justify itself – but if you shifted even 20% of the military's spending to a domestic public works department, all that money would not only be to the benefit of the U.S. taxpayer, but you could hire tens of thousands more American workers to do the jobs. It's a win-win for everyone. And it's probably something a lot of legislators could get behind.
Not only that, but a federal public works department would quickly be able to aggregate learnings on improving efficiency – knowing what works and what doesn't – while also being able to wield the power of the federal government to negotiate lower prices.