"We've come through the dot.com bubble, the housing bubble, and I'm very concerned about us having a government bubble," Sen. Sam Brownback, R-Kan., told Federal Reserve Chairman Ben Bernanke during a meeting Wednesday of the Joint Economic Committee of Congress. Brownback also suggested that the United States use trade policies and possible sanctions to force China to change its exchange rate policy, which Brownback said contributed to the imbalance of trade. And Brownback recommended that the Fed allow interest rates to move up as a show of faith in the strength and resilience of the economy. Brownback later questioned Bernanke on the possible impact of the nation's debt and deficits. Bernanke responded: "At some point, the markets will make a judgment, really not about our economic capacity but our political ability, our political will, to achieve longer-term sustainability. . . . We don't know when that point would be reached."