Washington ? After years of relative calm on the inflation front, Americans are being battered by $2-a-gallon gasoline, rising food prices and higher medical bills. And there are fears that price pressures could worsen in 2005.

The problem came into sharp focus last week when the government reported that wholesale prices increased in October by the largest amount in more than 14 years, and prices at the retail level recorded the biggest gain since May.

At the same time, energy prices experienced another jump, climbing at an annual rate of 22.5 percent through October. This has contributed to inflation’s rising at a 3.9 percent annual rate this year, compared with 1.9 percent in 2003.

Inflationary pressures have led some economists to worry about a possible nightmare scenario: The dollar weakens dramatically, which drives up import prices; as terrorists attack overseas oil production facilities, which drives up energy prices; and like that, America’s productivity miracle, a main reason for moderate inflation in recent years, disappears.

Economists acknowledge this is a worst-case scenario. Still, they say some shock is likely.

“If my inflation projection for next year goes haywire, it will most likely be because of external factors such as geopolitical tensions or terrorism that we have no control over,” said Sung Won Sohn, chief economist at Wells Fargo in Minneapolis.

Some economists see inflationary pressures next year that will result directly from Bush administration policies on the dollar.

The administration insists it favors a strong dollar yet has done nothing to check the greenback’s slide over the past three years. This decline could help combat the widening U.S. trade deficit by making American products cheaper abroad and imports pricier in this country.

Treasury Secretary John Snow and other U.S. officials have pressed China to sever its currency’s direct link to the dollar. U.S. manufacturers contend that practice has undervalued the Chinese currency by as much as 40 percent and given China a substantial advantage against U.S. competitors.

If China should allow financial markets to set the value of its currency, that could mean steep price increases for the billions of dollars in imported Chinese products — from sneakers to high-tech electronics — that U.S. consumers have grown to love.

The threat of higher inflation will come not only from China but other Asian countries. They fear a loss of export sales because of China’s currency manipulation, so they have managed their currencies to keep them from rising against the dollar.