"It's going to be a bit of a different story," the London-based economist said. "In recent months there's been quite a bit of evidence that the U.S. economic recovery may have shifted up a gear."
However, the recent inflation trend is good news at least to those who will be deciding monetary policy.
The largely dovish Federal Reserve has been adjusting its benchmarks for when it will consider raising rates, and a tame inflation environment makes the decision considerably easier. The Fed's Open Market Committee has an easier time justifying near-zero short-term rates while inflation is low even as the unemployment rate drops.
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The FOMC will issue its most recent policy statement Wednesday at 2 p.m. EDT, followed a half hour later by a news conference with Chair Janet Yellen.
"These are great numbers for the Fed," Joseph LaVorgna, chief U.S. economist at Deutsche Bank, said in an interview. He cautioned, however, not to look at the data as indicative of stagnation.
"Your concern about disinflation has to be based on what your growth forecast is," he said. "The bulk of the data has been better than expected. As long as that's your baseboard, you can look at today's (CPI) data and say this isn't a trend likely to persist."
Economists point to a few key factors that further exemplify the difference: While both nations have an aging population, Japan actually has seen a decline in total numbers, tamping down demand; productivity, while low in the U.S., also was falling consistently in Japan; and forecasts do show the U.S. economy growing, albeit slowly, rather than declining like in Japan, which saw a 7.1 percent gross domestic product plunge in the most recent quarter.
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"I don't think it's a totally fair comparison, especially not at this point. Let's make sure we have the right context," said Tom Porcelli, chief U.S. economist at RBC Capital Markets. "We basically doubled our inflation rate in the last few years."
Yet the overall lackluster inflation growth should be enough to keep the Fed strongly in the easing game.
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"It seems clear that the U.S. economy has been stripped of so much productive power that the only real option for historically acceptable economic growth for the time being is monetary policy trickery," said Alan Tonelson, an economist who writes the policy blog, "Reality Chek." "There are still some differences between the U.S. and Japanese economies that justify caution in warning that this country is headed for a Japan-style deflation trap."
—By CNBC's Jeff Cox