Throughout American history, the story of immigration has been tinged by emotions and fear as millions of people abandoned the old and took a brave and often risky leap into the new. It has also been a tale of remarkable cultural blending. Less well understood but still important, immigration has been a story of economics. From the Europeans who fled war and famine in earlier epochs to the Latin American, Asian and other immigrants of today, new arrivals are often strivers, entrepreneurs, innovators and just plain hard workers.

This grand historical experience is the secret behind the dry numbers in a new report by the Congressional Budget Office that estimates the fiscal and economic impact of the immigration reform legislation taking shape in the Senate. Not surprisingly, budget analysts found that a net increase of 10.4 million people living in the United States over the next decade, and an increase of 16 million over 20 years, would be a tremendous shot in the arm. The CBO has confirmed a gritty street truth about immigration: For all the difficulties and burdens, it is a net plus to the economy. Every senator and congressman who has campaigned in recent years for more economic growth and productivity, or who has railed against the budget deficit and lamented the slow recovery, ought to read the sober and persuasive assessment of the CBO on immigration reform.

Sure, more people means more spending on health and welfare. The CBO found that over the next decade direct spending would increase by $262 billion if, among other measures, the Senate immigration bill is passed, opening a path to citizenship for many of the 11 million immigrants now in the United States illegally. But at the same time, the CBO calculated that with so many more people working, revenues would soar by $459 billion over the same decade; the federal deficit would go down by almost $200 billion. Likewise, the CBO found the legislation would boost the country's overall economic output by 3.3 percent over the next decade, and by 5.4 percent over two decades, compared with what it would be without reform.

The CBO's estimates stand in stark contrast to a dubious Heritage Foundation study warning that immigration reform would become a fiscal black hole. The Heritage report views immigrants as burdens, not as strivers. This myopic and regressive outlook has been proved wrong by generation after generation.