But the "free market theme" is an illusion, since the interbank lending rate is a function of how much base money is available to banks, and base money is by de

But the "free market theme" is an illusion, since the interbank lending rate is a function of how much base money is available to banks, and base money is by definition the money not produced by "free markets". The alternative of trying to fix the money supply growth and let the rate "float" doesn't look less like government intervention, and it does involve a lot more wild lurches in interest rates and bank/company failures.