The Fed's decision to continue its $85 billion-per-year asset-purchase program unabated caught much of Wall Street by off-guard, but there was another unexpected element in its announcement, Brian Kelly of Brian Kelly Capital said Wednesday.
"The other thing that was surprising to me today is how much (Fed Chairman Ben) Bernanke focused on the fiscal drag, from the sequestration, from the debt-ceiling debate," he said. "I think that was a bigger factor in today's decision than the markets making out, and that then that goes to if you have some kind of a grand bargain, that would actually be bad for the market.
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"And he mentioned the drag that we had. It's about 1 percent of GDP. So, I think what he's saying is, 'Keep my foot on the accelerator.'"
On CNBC's "Fast Money," Kelly said that he had expected "at least $10 billion" fewer purchases of U.S. Treasury bonds and mortgage-backed securities.
Tim Seymour of EmergingMoney.com cited less uncertainty from Syria and the candidacy of Larry Summers to succeed Bernanke as Fed chairman as a significant factor.
"No war. No Summers. No taper. No fear," he said. "So, people going into still a lot of significant events are short volatility here and got even shorter."
Seymour said he "would be getting long vol."
StockMonster's Guy Adami added another "no."
"No earnings growth," he said.
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"I think that still is a trade, looking for an opportunity to get short this because guess what? The world still hasn't changed to Caterpillar's benefit on this one," he said. "This has just been a short-covering rally."
The S&P ended the day at an all-time high of 1,725.52. The set a record, closing at 15,676.94.
Dan Nathan of RiskReversal.com noted that the market had been "consistently" making higher highs and higher lows ahead of the Fed's announcement.
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"A lot of people got caught offsides here," he said. "So, the way I'm trading this here is if you were already positioning for a better U.S. economy and a better global economy and you're going into cyclicals and some laggards, then I think you can still do that here because … today's news doesn't put off taper forever.
"They still may do it sometime very soon. And they're going to do it when they actually have more confidence than they do right now."
Trader disclosure: On Sept. 18, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Dan Nathan is long NFLX; Dan Nathan is long IBM; Dan Nathan is long TSLA; Dan Nathan is long CAT; Dan Nathan is long MSFT; Dan Nathan is long FXI; Dan Nathan is long WFM; Dan Nathan is long ZNGA; Dan Nathan is long XCO; Dan Nathan is long SPY; Tim Seymour is long BAC; Tim Seymour is long INTC; Tim Seymour is long NOK; Brian Kelly is long oil; Brian Kelly is long natural gas; Guy Adami is long C; Guy Adami is long GS; Guy Adami is long INTC; Guy Adami is long MSFT; Guy Adami is long AGU; Guy Adami is long NUE; Guy Adami is long BTU; Guy Adami's wife, Linda Snow, works at Merck.