Most Americans think their country is the best in the world — but global studies paint a murkier picture. Here's everything you need to know:

Is the U.S. No. 1?
It is economically. The U.S. is still comfortably the largest global economy, with a GDP of more than $17 trillion; second-ranked China's is only $10 trillion. The U.S. has an average after-tax household income of $41,355 — the highest of any of the 34 nations in the Organization for Economic Cooperation and Development (OECD), and considerably more than the group's median of $27,630. All five of the world's largest companies by market capitalization — Apple, Microsoft, Exxon, Berkshire Hathaway, and Google — are American. But in its annual study of well-being in developed nations, the OECD found that material wealth was just one component of happiness. "When you have satisfied your basic needs in terms of income, you tend to believe there are things that matter much more than income," says Romina Boarini, head of the Measuring Well-Being and Progress Section at the OECD. "People want quality of life." In terms of overall well-being, the organization found, the U.S. is not No. 1. In fact, it's not even in the top 10, coming in at 15th.

Why is that?
For two primary reasons: A lot of Americans are isolated and feel a lack of social connection; and our poor work-life balance. Full-time American employees work longer hours than those in any other developed nation — an average of 46.7 a week, according to a recent Gallup report — and take fewer vacation days. They also generally enjoy less sleep and leisure time — an hour a day less than the Germans, for example. Our health isn't great, either. The U.S. is easily the fattest nation in the group, with 35 percent of adults either overweight or obese; in Japan, it's just 4 percent. Our wealth is distributed very unevenly; as a result, we have high rates of childhood poverty, and the third-highest birth rate among 15- to 19-year-olds, behind Mexico and Chile. America's murder rate — about five per 100,000 people — is the second-highest in the OECD, behind only Mexico's.

What do other surveys say?
The U.S. is in the middle of the pack in all of them. The U.S. fell from 12th to 23rd in Gallup's most recent well-being index, which found far more happiness in many Latin American nations, including Panama, Costa Rica, and Belize. Why? Social cohesion is strong in these nations, Gallup says, and people there are most likely "to report daily positive experiences such as smiling and laughing, feeling enjoyment, and feeling treated with respect each day." The U.S. comes in just 11th on the U.K.-based Legatum Institute's annual prosperity index, which rates Norway and Switzerland at the top. In that survey, U.S. crime rates pushed us down in the rankings: Some 17 percent of Americans said they'd been a victim of theft — comparable to Nicaragua, Panama, and Brazil — while only 74 percent said they felt safe walking alone at night, a level of insecurity comparable to Egypt's and Serbia's.

Which countries are happiest?
Well-being studies are consistently topped by the Nordic countries — the Scandinavian trio of Denmark, Norway, and Sweden, along with Finland and Iceland. The so-called Nordic Model involves high taxes and universal social welfare. In Denmark, for example, everyone receives free national health care; by law, new mothers get 18 weeks' fully paid maternity leave; and students pay no tuition. These benefits don't come free, of course: Top earners pay as much as 57 percent income tax, while those in the middle brackets fork out up to 48 percent. Because of high taxation, consumer goods are far more expensive: a new iPhone 6S, which costs $650 in the U.S., costs more than $1,000 in Denmark. But the Nordics generally like life under their system. In the U.N.'s most recent World Happiness Report — which ranked Switzerland No. 1 — the Nordic nations ranked second, third, fourth, sixth, and eighth. The U.S. was 15th.

What do these indexes tell us?
Happiness is very subjective, making it hard to rank nations that have widely differing value systems. Americans have always put a high value on personal liberty, individual autonomy, and climbing the economic ladder; as a result, we have more discretionary income and consumer goodies than nations rated as happier. "We cannot all be like the Nordics," says MIT economist Daron Acemoglu. But there is something we can learn from the Nordics and the Latin Americans. Studies have found that in general, the "golden triangle" of happiness consists of financial security, a sense of purpose in life, and strong personal relationships and social connections. "People are social creatures and get pleasure from spending time with others," Boarini of the OECD said. To be happier, experts suggest, Americans should work a little less, spend more time with friends and family, and become more deeply engaged in organizations and their communities.

Seeking 'gross national happiness'
Since 1971, the tiny Himalayan country of Bhutan has refused to use GDP as the overarching way to measure progress. Instead, the nation has focused on "gross national happiness." By asking its citizens about how they feel on a variety of indicators — from health and education to emotional fulfillment and the environment — officials determine where to focus their attention and funding. In 2011, the U.N. passed a resolution encouraging other countries to follow Bhutan's example. Four U.S. states — Maryland, Vermont, Oregon, and Colorado — now use a "genuine progress indicator" that works along similar lines. But opponents are pushing back, arguing that Bhutan's system has failed to deliver results. Most citizens remain impoverished; political corruption is widespread; suicide rates are high. Bhutan's government may even be cooling on gross national happiness: Prime Minister Tshering Tobgay has called the concept a "distraction." But the U.N. is still a believer. "Happy people live longer, are more productive, earn more, and are also better citizens," the organization noted in its 2013 World Happiness Report. "Well-being should be developed both for its own sake and for its side effects."