Quote from Thunderdog:
I expected that someone would make that comparison sooner or later, and I think it is flawed. Communism would never work in the real world because it blunts ambition and initiative. Because human achievement and economic progress are predicated on ambition and initiative, communism does not even really work on paper. It is theoretically flawed. Keynsian economics relies on intellectual honesty and discipline, which is at least conceivable, if not necessarily probable, in the right hands.* Therefore, I think it is at least theoretically possible to successfully implement, unlike communism, which dies on paper. Perhaps I'm putting too fine a point on it, but I'm not a fan of broad brushes. Again, let me state that I'm not big on economic theory, but I try to approach it honestly.
*And at the end of the day, unless a country's finances are addressed with intellectual honesty and discipline, then any approach under any label will likely result in a shambles. Meanwhile, those who wish to rely solely on the "invisible hand" can take their cue from a host of Third World countries for inspiration.
I'll try to summarize it:
Communism assumes the masses will be motivated by altruism.
Keynesian economics assumes politicians will be motivated by altruism, honesty, and intellectual discipline.
Small-government capitalism assumes both people and politicians will be motivated by self-interest and ambition.
Which do you think fits true human nature in the real world?
In my opinion, Keynesian economics is even *less* likely to work than communism, because politicians on average are less altruistic and honest than the general population. They are motivated by getting votes, getting power, getting big budgets, and patronage, far more so than by intellectual discipline and honesty. Keynesian economics might work better in a benign dictatorship - but we all know those are rare, and the few that have ever existed die out as soon as the dictator dies and gets replaced with a selfish dictator (which is 98% of them). The only reason Keynesian economics has not been disastrous is because it only tries to affect a portion of the economy at certain times, rather than the entire society at all times.
Because of politicians incentives and thus actions, Keynesian economics always degenerates into wasteful boondoggles and patronage, and you get a huge amount of boondoggle fiscal drag and fiscal bribery/vote-buying over the course of the cycle. Instead of running budget deficits in recessions and surpluses at all other times, they run deficits at all times except huge booms, and run monster deficits in recessions. IMO the cause is entirely predictable in theory, given our knowledge of human nature. It's just as predictable as how communism will work out if it's ever tried again.
Because of this inherent nature of the political class, any system apart from the nightwatchman state will inevitably have huge wastage for its entire lifetime. And IMO the wastage will always trend up. We've seen that with every democracy that has ever existed. As long as people think that social democracy is the ideal political system, social groups will continue fighting for their share of the tax revenue pie, and competition will ensure that this pie gets bigger and bigger until you end up in quasi-socialism anyway. The USA is already socialist by 19th century, or even 1920s standards.