Governments are surely exactly the place most super-long-term projects have to happen (and typically have happened). It's pretty hard for a corporation to convince shareholders to invest in something that won't pay dividends for 15-20 years. Religious organizations building cathedrals is probably a rare example of it happening below the state-level (it's hard to imagine without belief in higher powers or an afterlife etc. why many people would thoroughly commit themselves to a project they won't see completed in their lifetimes).