The Federal Reserve, by setting a single interest rate for the entire economy, destroys local market signals. (What you want is a locally adjusted rates to reflect natural cycles in decoupled local economies - this is what happens if you don't regulate centrally.)
The government's monopoly on the issuance of currency is important, too. And what about the SEC that went after innocent people like Martha Stewart and ImClone founder Sam Waksal, while blind to actual crooks such as Bernard Madoff? What about the federally-owned Fannie Mae and Freddie Mac? They were to a large extent responsible for the housing crisis. They have so much of the market, and it's government regulation and backing that gave it to them.
On a national scale, private business, if devoid of these corrupting government influences, would not fail all at once, nor would it fail with such lasting severity as we've seen in the last century. It's notable that all of the regulatory bodies (and a great many more that I did not mention) were created in the last 100 years to "stabilize" the market - but it doesn't take great genius to see that all they have accomplished is to take little local pockets of boom/bust (which add up to overall growth and stability on a national scale), and pack them into huge booms and busts that cause much longer and deeper cycles that you can't escape from as easily by moving to a new city.
And don't forget that this sort of centralization is important for marshaling resources necessary to run an expansionist empire (think about the economic policies in America during the two world wars, and the American empire that resulted).
To help differentiate between the "capitalism" the article smears (what should be called a mixed economy - some capitalism, some regulation), and actual capitalism, see http://www.capitalism.org/.