Fed Chairwoman Janet Yellen threw a 3-2 curve ball to the markets on Thursday afternoon by saying the Federal Open Market Committee would not raise rates, and the markets’ knees buckled.

The headline on John Crudele’s column in The Post Friday said it all: “Fed Chickens Out.”

It was a very unclear lead-up to the almost historic meeting, with about half of the Street economists expecting a hike. But what ensued after the announcement will surely hurt the Federal Reserve’s credibility for some time to come.

For the first time — with the US in a non-crisis mode — the Fed highlighted another country’s slowdown and allowed it to influence its decision not to raise rates from our crisis level of zero.

The problem with the Fed being overly sensitive to China’s growth plight is simple. The Chinese do not give a rat’s ass how the US economy does as long as China grows. So why should we show deference to it, when our economy is certainly strong enough for a 25 basis-point rate rise?

With all the Fed concern about the market’s short term volatility from China, did the Fed realize that by bowing to the Chinese economy, we could end up importing their volatility. On Friday, Shanghai and Hang Seng were up slightly while the Dow lost 290 points.

Perhaps China is a straw man.

From the first paragraph of Yellen’s statement: “Since the Committee met in July, the pace of job gains has been solid, the unemployment rate has declined, and overall labor market conditions have continued to improve.”

Remember, when the Fed was led by Ben Bernanke and Yellen was vice chairwoman, they told us to expect a rate hike once unemployment got below 6.5 percent. Then the excuses came.

Today the jobless rate stands at 5.1 percent. Now, I know the unemployment rate is a complete joke of a statistic. But does Yellen realize this too and prefers to be politically correct and not say so?

Why not just pull the Band-Aid off? The fear of the raise is far worse than any 25 basis points.