On the day after an unusually important Fed policy meeting both gold and stocks severely rebuked the central bank’s decision to take no action in support of the weak dollar or to curb rapidly growing inflation.

Gold spiked $30, a clear message that Bernanke & Co. won’t stop inflation. Stocks plunged over 200 points, an equally clear message that the Fed’s cheap-dollar inflation is damaging economic growth.

These market warnings are two sides of the same coin. Inflation, which is caused by excess dollar creation, is the cruelest tax of all. It is a tax on consumer and family purchasing power. It is a tax on corporate profits. It is a tax on the value of stocks, homes, and other assets.

Crucially, the capital-gains tax — the most important levy on all wealth-creating assets — is un-indexed for inflation. Hence, long before Barack Obama or Congress can legislatively raise the capital-gains tax rate, rising inflation is increasing the effective tax rate on real capital gains. That’s an economy-wide problem.

By doing nothing at the June 25 meeting the Fed turned its back on the very inflation-tax problem it helped create. The spanking it received from the markets was well deserved.

Former chairman of the Fed, Paul Volcker, who is advising Senator Obama’s presidential campaign, issued a stern warning at the New York Economics Club a few months back. He said inflation is real and the dollar is in crisis. Soon after, Fed head Ben Bernanke changed his tune in public speeches, pledging greater vigilance on inflation and hinting at a defense of the dollar. Treasury man Henry Paulson and President Bush also stepped up their rhetoric regarding a stronger greenback.

But words were no substitute for actions this week.

It is an interesting historical footnote that Paul Volcker still is highly regarded as the greatest inflation fighter of our time. Working with Ronald Reagan, it was Mr. Volcker who slew the inflation dragon in the 1980s. Indeed, the combination of tighter monetary control from the Fed and abundant new tax incentives from Reagan launched an unprecedented 25 year prosperity boom characterized by strong growth and rock-bottom inflation. At the center of the boom was a remarkable 12-fold rise in stock market values, a symbol of the renaissance of American capitalism. But that was then and this is now.

Talk of major new tax hikes is in the air today, while the inflationary decline of the American dollar is plain fact. It’s as though our economic memory is being erased, both in tax and monetary terms. Staunchly optimistic supply-siders Arthur Laffer and Steve Moore are even finishing a book on the subject. Called “The Gathering Economic Storm,” its concluding chapter is titled: “The Death of Economic Sanity.”

The Volcker anti-inflation model presumably handed down to Alan Greenspan and Ben Bernanke always argued that price stability is the cornerstone of economic growth. Yet it appears that today’s Fed has reverted to a 1970s-style Phillips-curve mentality that argues for a trade-off between unemployment and inflation, rather than the primacy of price stability.

History teaches us otherwise. It states that since rising inflation corrodes economic growth, inflation and unemployment move together — not inversely. Even in the last 18 months this is proving true. Inflation bottomed around 1% in late 2006. Unemployment bottomed at 4.4% about 6 months later. Today, the CPI inflation rate has climbed to more than 4%, wholesale prices have jumped to 7%, and import prices have spiked to 18%. Unemployment, meanwhile, has moved up to 5.5%.

Over the past five years the greenback has lost 40% of its value. Oil is close to $140 a barrel. And gold, now trading above $900 an ounce, is warning that if the Fed fails to stop creating excess dollars, inflation could rise to 6% or 7%. I had hoped Mr. Bernanke would show his inner Volcker at Wednesday’s meeting. He didn’t. While the Fed acknowledged that “the upside risks to inflation and inflation expectations have increased,” it took no action taken to raise the fed funds target rate, which now stands at 2% and is actually minus-2% adjusted for inflation. Even a quarter-point rate hike — merely taking back the last easing move in April — would have been a shot heard ’round the world in defense of the beleaguered dollar. It didn’t happen.

Only Richard Fisher, president of the regional Dallas Fed, dissented in favor of a higher target rate. That leaves the hard-money Fisher as the lone remaining protégé of Paul Volcker.

Of course, if Fed policymakers reconvene immediately to right their wrongheaded mistake, the value of our money could be quickly restored. The next scheduled Open Market meeting is August 5, but they needn’t wait that long.

Let’s hope they come to their senses.

Mr. Kudlow is host of CNBC’s “Kudlow & Company.” © 2008 Creators Syndicate, Inc.