How does the government cause downturns?

By doing stuff like "guaranteeing" student loans, encouraging policies of buying homes with high credit, getting the Fed to lower interest rests too much (making credit so cheap and easy companies don't even use their profits to buy/invest in stuff anymore; they even use credit to buy back their stock. Insanity), etc

All of that distorts the market and makes everyone spend money they don't actually have. Eventually all of this catches up with everyone, on a country-wide scale.

==makes everyone spend money they don't actually have.==

So much for all that personal responsibility we used to hear so much about. Far easier to blame the government for everything.

Companies use credit to buy back stock because we deregulated that activity. It used to be that the government didn’t allow it. This point is actually a counter-point to your theory.

By trying to fix the economy in one area and ignoring the effects of the fix in a bunch of other areas.

Oh right, the free market should fix this!

/s

who knows more - a large number of people who have no idea what they're doing or a small number of people who have no idea what they're doing?

Let's pick EPA for a second here. It's a bit rich to claim they have no idea what they are doing and should be abolished because the free market would fix the world around it.

For example, let's cherry-pick the Clean Air Act and its effects: "In addition, because air quality across the United States improved; it is estimated 205,000 premature deaths and millions of other respiratory complications were prevented which resulted in an economic savings of $50 trillion versus the $523 billion invested to meet the Clean Air Act standard."

https://en.wikipedia.org/wiki/Clean_Air_Act_(United_States)#...

Randian economics is not a solution.

All this "growth" is largely driven by the debt and grand wisdom of the Fed's monetary policy. Those closest to the money printing press get undiluted gains and by the time that money circulates back down to the general population, they are robbed from their wealth by devaluing the currency. Furthermore, looking at the money supply, the banks aren't actually distributing and lending out that capital like they should. Long story short this is a direct causation of government policy.