[splitrocket]

Many of the things mentioned above were in fact produced without government intervention by private enterprise before the widespread adoption of the government funded projects. They were not, however widely adopted, nor resulted in the technologies you are using on your computer sitting in front of you.

There is a reason why people joke about selling bridges yet simultaneously rely on bridges for their commutes in and out of work: some things, if you try to make them profitable from the get-go will never achieve the scale necessary for them to provide utility. One of the many functions of Government is to provide a mechanism for the economy to move beyond a suboptimal economic maxima. Spending money on infrastructure, like bridges, does exactly this. No private firms will build a bridge because they can't make money off of it, but all private firms benefit from the increased availability and mobility of labor. The pre-bridge state of affairs is a suboptimal maxima. (Protip: WWII military spending enabled the US to escape the suboptimal maxima of the Great Depression. That is, government spending, of which, military spending is among the least effective at creating jobs and improving the economy.)