NEW YORK (CNN/Money) - The most important thing about the Federal Reserve's meeting and policy statement today is not what they did - hike the key short-term rate to 2.5% - but what they did NOT do: confirm the inflation-worry hysteria that had circulated in some parts of the bond market.

In fact, the Fed's policy statement, where they line up a bunch of finely-nuanced words and phrases to show what they think about the economy now and where rates could go next, was all but identical to the statement issued after their last meeting on December 14 of last year!

"Inflation and longer-term inflation expectations remain well contained." That's what the Fed said today and last month and in November. No change at all.

Now, it's possible that Big Fed Chief Alan Greenspan is waiting for his testimony to Congress on February 16 and 17 to "officially" signal to the world that he and his monetary policy gang are getting more worried about inflation. Or maybe not.

Greenspan's main inflation gauge, the "PCE deflator" is rising at a 1.5% annual rate as of January, hardly what you would call a flashing red light on the price pressure front. And productivity, worker output per hour, has held up okay and that's also seen as an inflation blocker.

Does the Fed think that the economy is getting ready to overheat? Not if you look at today's assessment (which did not change from December, remember?). It says output is growing at a "moderate" pace in spite of higher energy prices, and labor market conditions continue to improve "gradually." And if it's describing growth this way, it would not seem to hint at policymakers itching to start raising rates more quickly.

And ultimately that's what the bond world is nervous about. The Fed has raised its key short-term rate six times, from 1% to 2.5%, and the 10-year government note yield has stayed low, today around 4.15%. Had the Fed signaled a move to more aggressive rate hikes, that could have sent the 10-year note moving higher again, causing big bond investors to lose money (because bond prices fall as bond yields rise).

And ultimately that would boost long-term mortgage rates, and maybe even slow down the economy.

Some say the reason why long-term rates stay low is because the Japanese and Chinese -- who get lots of our dollars because we buy lots of their goods -- buy lots of our bonds. Others say it's because inflation is low and the Fed's actions will keep it that way.

One thing for sure, if the Fed had dropped the word "measured" in describing in how it's going to raise rates, it could have helped send long-term rates higher. It may be that the Fed doesn't mind seeing long-term rates low to maintain that extra support for the economy. Let's hear what Mr. G. says in a couple of weeks.

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-- Kathleen Hays is economics correspondent for CNN and contributes to Lou Dobbs Tonight.