It's possible that the collapse of the bridge in Minneapolis will bring on another era of concern about "crumbling infrastrucure," similar to a burst of interest I remember in the 1980s. It seems that the last couple of times the bridge was inspected there were signs of fatigue, and there were desultory plans to replace it, perhaps in 2020. And it turns out there are a lot of bridges around the country in states of relative disrepair. I just heard Massachusetts Rep. Barney Frank talking about how we could fix this stuff if we just pulled out of Iraq and raised taxes on the "rich" even more -- and arguing that there are certain things only the government by "pooling our resources" can do.
As the discussion moves forward, it would be well to remember that maintenance and repair of infrastructure is something government notoriously does very poorly. It's not hard to see why. It's a matter of incentives. Maintenance is not sexy or glamorous and it doesn't buy votes or give politicians the chance to preside at ribbon-cutting ceremonies, as building new things does. So the temptation is always to postpone maintenance or relegate it to a lower priority.
It's not the case that the private sector can't build infrastructure; it does it all the time, from building roads and sewers when new developments go in to building (yes) bridges. Chances are, although the money to rebuild the Minneapolis bridge will come from government, that the actual work will be done by a private company (for more money than necessary, given that public works contracts are typically pork-laden or go to those with connections).
There are only a few private highways in the U.S. (interestingly there may be more in Singapore or China) but they are almost always better maintained than government projects, because paying customers will demand it. When the costs are diffused and confused, which is what happens when we use the coercive power of government to "pool our resources," responsibility is diffuse and there's little relationship between good maintenance and political success.