Washington PostAmerican lives are shorter on average than those in other wealthy nations, and the gap is growing ever wider, the latest data released by the Centers for Disease Control and Prevention show.As recently as 1979, the typical American could expect to live about 1.5 years longer than the average resident of one of the other countries in the Organization for Economic Co-operation and Development, a group of 35 wealthy, predominately Western nations.The typical American baby born in 1979 could expect to live about 73.9 years, while the typical baby born in one of the other 34 OECD countries would live roughly to age 72.3. But by 2015, that gap had flipped. The average American born that year could expect to live a little less than 79 years, compared to nearly 81 years in an OECD country.In 2016, U.S. life expectancy dropped for the second year in a row, which hasn’t happened since the early 1960s. Numbers for the remaining OECD countries aren’t yet available, but if prior trends continue, the gap between the United States and the rest of the wealthy world is likely to grow even larger.Part of the reason for the trend is the U.S. health care system. Americans spend thousands of dollars more per capita on health care than any other country in the world, but in return they live shorter lives than people in most other rich nations.While the care itself is generally quite good, access to it remains spotty: The United States is the only OECD country without some sort of universal health care coverage, and as a result millions of Americans currently have no form of health insurance. The recent repeal of Obamacare’s individual mandate will cause that number to swell by millions in the coming decade.Violence is also taking a toll. The U.S. homicide rate has been steadily falling since the early 1990s, but Americans are still more likely to be murdered than people in nearly any other rich nations. A 2016 study found that the "U.S. homicide rates were 7.0 times higher than in other high-income countries, driven by a gun homicide rate that was 25.2 times higher." Easy access to guns is the big factor there.A 2014 review noted while plenty of individual factors lurk behind our short life-spans — tobacco use, obesity, violence and disease among them — the lion’s share of the difference between American life-spans and those in other countries can be explained by "variations in non-medical determinants of health, some of which result from dramatic differences in public policies across the U.S. and other OECD countries."Among other things, that study noted:•??The United States spends far less public money on early-childhood education and care than nearly any other OECD country.•??The United States is the only high-income country in the world that does not mandate paid maternity leave, as well as sick leave and vacation time.•??U.S. unemployment benefits are less generous than in most other OECD countries.•??Housing assistance in the U.S. is far below other wealthy nations’.A study published in December 2016 found that if these and other social welfare factors were brought up to the OECD average, it would add nearly 4 years to U.S. life expectancy. "The U.S. mortality disadvantage is, in part, a welfare state disadvantage," the authors concluded.Americans are dying younger, in part, because of policy choices made over the decades: rejecting single-payer health care; cutting taxes for the rich; shunning universal basic income; abandoning universal child care.