Tim Roemer, a former U.S. representative from Indiana who served on the Sept. 11 Commission, is a senior vice president at APCO Worldwide.

When I went to serve as U.S. ambassador to India in 2009, I hoped to learn more about that country’s vibrant democracy and our shared values. I gained an additional benefit while overseas: I learned that America is still deeply admired around the world and the place where many people want to live out their dreams. Consequently, I have been appalled by the gloom of those predicting that America’s greatest days are behind us. These sentiments seep through our society, from pundits to parents at my daughter’s basketball game, as people complain they are “despondent” and “depressed” that our children will be left behind by the United States’ “decline.”

Frustration at current conditions is understandable. Millions of Americans are out of work. Our trade deficit runs about $44 billion per month. The news is filled with stories of greed and corruption. Congress is paralyzed by partisanship. Meanwhile, we hear that India and China are outpacing us in infrastructure, technology and manufacturing capability, and investment.

But living overseas, I saw that ours is not the only country facing profound challenges. Most major powers are experiencing similar or bigger problems. True, we feel the pain of our setbacks and fear that we are losing ground. Yet when I met Indian students at schools or living in slums, they consistently told me America is the place where they most want to study. Rather than underselling our historical record and natural resiliency, we must build on these assets.

The United States has the largest and most technologically powerful economy in the world, a per capita gross domestic product of $47,200 and a gross national purchasing power that equals those of China and Japan. Our national economy is bigger than those of Russia, Britain, Brazil, France and Italy combined.

Our huge GDP is no accident. We have a market-oriented economy where most decisions are made independently by individuals and individual businesses. From Robert Fulton to Thomas Edison to Bill Gates and Steve Jobs, inventions spring from our labs, universities and garages, and eventually propel world growth. Meanwhile, in China, government still peers over the shoulder of inventors and ordinary Internet users. India still fights a legacy of corruption in too many places, at too many levels. In Europe, red tape has stifled many small businesses.

During a meeting in Mumbai with three dozen business millionaires in their twenties and thirties, I asked a simple question: Which market would you most like to access? Almost unanimously, the answer was the United States. U.S. companies remain world leaders in information technology, bioscience, nanotechnology and aerospace. The evidence is clear not only in the development of products such as the iPad and iPhone but also in new patents. Last year, U.S. firms captured more than 50 percent of all U.S. patents; they received twice as many corporate patents as Japan, which came in second.

Yes, our high schools need to do better, as reading and math scores and dropout rates show. But when it comes to higher education, we remain a beacon of success. Four of the world’s top five universities, and seven of the top 10, listed in last year’s Times Global Higher Education Rankings are in the United States. Americans have won 333 Nobel prizes, almost triple the number of Britons, the runner-up. In the past three years, Americans have won Nobel prizes in such critical fields as economics, physics, medicine and chemistry.

Even immigration, a topic of some tension, continues to enhance our competitiveness. Highly capable and legal immigrants flock to our country — aiming not for Ellis Island but Silicon Valley and the Research Triangle Park. As researchers at Duke and the University of California at Berkeley showed in 2007, 25 percent of U.S. tech and engineering start-ups between 1995 and 2005 had one or more immigrant key founders, whose companies collectively generated an estimated $52 billion in 2005 sales and created nearly 450,000 jobs.

Since the time of railroads and canals, our often-maligned federal government has invested in vital research in early phases for developing technologies, such as the Internet and energy technology, helping build a head start for the next generation of U.S. industry.

Other advantages include our positive demographic growth pattern, our environmental protections of water and natural resources, and, as demonstrated by the smooth operation that took out Osama bin Laden, incredible military skill.

This country faces real challenges, including a growing deficit, crumbling infrastructure and unsustainable entitlement spending. Addressing these issues will require leadership to meet the times, as happened during the Civil War, the Great Depression, World War II and the civil rights era. Leaders need to exhibit the spirit captured by Theodore Roosevelt when he reminded us that “aggressive fighting for the right is the noblest sport the world affords.”

My experience in India reinforced the perspective of America’s image as a country of tomorrow. We should be heartened, not distressed, by the Tea Party and Occupy Wall Street movements. These activists remind us our country is worth fighting for. During this election year, we have the renewed opportunity to channel our feelings about country — love, fear, anger and hope — into action to transform problems into solutions and move closer toward a more perfect union.