The same pattern can be found across a range of government programs. The reason is always the same: their relatively small size. Over all, government cash benefits in the United States — including pensions, disability, unemployment insurance and the like — contribute about 10 percent to household income, on average, according to the study. The average across industrial nations is twice that.

Our budget reveals a core philosophical difference with other advanced countries. In the big-government social democracies like those of Western Europe, government is expected to guarantee a set of universal public services — from health care to child care to pensions — that are considered basic rights of citizenry. To pay for this minimum welfare package, everybody is expected to contribute proportionately into the pot.

Government in the United States has a different goal. Benefits are narrower. Social Security and Medicare follow a universal service template, but only for older Americans. Other social spending is aimed carefully to benefit the poor. Financed through a more progressive tax code, it looks more like charity than a universal right. On top of that, our philosophical stance virtually ensures a small government.

Progressive taxes make it hard to raise money because they distort people’s behavior. They encourage taxpayers to reduce their tax liability rather than to increase their pretax income. High corporate taxes encourage companies to avoid them. High taxes on capital income also encourage avoidance and capital flight. High income tax rates on top earners can discourage work and investment, too. So trying to raise a lot of money with our progressive tax code would probably not achieve the goal and could damage economic growth.

Big-government social democracies, by contrast, rely on flatter taxes to finance their public spending, like gas taxes and value-added taxes on consumption. The Nordic countries, for instance, have very low tax rates on capital income relative to income from work. And they have relatively high taxes on consumption. In Denmark, consumption tax revenue amounts to about 11 percent of the nation’s economy. In the United States, sales taxes and excise taxes on cigarettes and other items amount to roughly 4 percent.

Liberal Democrats have long opposed them because they fall much more heavily on the poor, who spend a larger share of their incomes than the rich. But these taxes have one big positive feature: they are difficult to avoid and produce fewer disincentives to work or invest. That means they can be used to raise much more revenue.

Public finances are under strain today on both sides of the Atlantic, as governments struggle to cope with our long global recession and the aging of the baby boom generation. In Southern Europe, the pressure to pare back universal welfare systems is intense. In the United States, political leaders on both sides of the partisan divide have realized that even our relatively meager package of social goods cannot be sustained with our slim tax take.