As the nation approached Independence Day, a sweeping immigration reform bill was approved by the Senate by a vote of 68-32, with 14 Republicans voting in favor of the measure. The GOP-controlled House should do the same, before bipartisan goodwill fades.

The arguments used to postpone immigration reform are bogus. The positive aspects of the legislation far outweigh its flaws.

Consider, for example, the notion that the border needs to be “secured” first. Immigration already has fallen dramatically. In the case of Mexicans, net immigration had dropped to zero by 2011 and is likely negative by now—meaning more Mexicans have been going home than coming to the U.S. The number of undocumented Mexicans declined by almost 1 million between 2007 and 2011.

What is the main cause of this? While other factors may be at play, including improving economic conditions in Mexico, the main reason appears to be the weak U.S. economy. People aren’t coming to the U.S. because the economy is not producing enough jobs. Tightened border security appears to have played little role.

Despite a sharp increase in border patrol activities since 2000, including passage of the Security Fence Act of 2006, prior to the 2007 economic collapse the 10 states with the most immigrants saw their undocumented populations rise by half a million.

But as soon as the recession set in, the number of illegal entries dropped by two thirds and requests for H1-B visas—temporary work permits primarily for tech workers—decreased as well. This is consistent with what happened after the bursting of the bubble in 2000.

Opponents of comprehensive reform are now on the defensive. Zero or negative net immigration means either that the border is as secure as it will ever get in a democracy, or that immigration is so much more sensitive to the economy than to enhanced security that further efforts to secure the border are senseless.

Killing The Party

For their part, Republicans have a vested interest in passing immigration reform as soon as possible. To judge by the GOP vote among Hispanics and Asians, continued opposition to immigration reform could be suicidal.

While Latinos constituted 5% of the total vote in 1996, they represented 10% in the 2012 presidential elections. Together, Hispanics and Asians supported Democrats by a 3-to-1 margin.

If the perception persists that th e GOP is anti-immigrant, Hispanics could become a permanent Democratic constituency. This doesn’t have to be. Earlier GOP leaders had strong Hispanic support, including Ronald Reagan and George W. Bush, both of whom received close to 40% of the Latino vote.

The argument that legalized immigrants will become permanent Democrats mistakes the symptom for the cause. The cause of the disproportionate Democratic support is not party loyalty, but fear that Republicans are against immigrants. The Democratic support is a symptom of that fear. Postponing reform will deepen it.

The economic and cultural arguments against putting undocumented immigrants on a path to citizenship, and welcoming newcomers in the future, also have been disproved by reality.

Rather than take away native jobs, foreign workers have helped enlarge the economic pie. Economist Benjamin Powell, a senior fellow with the Independent Institute, estimates that immigrants, legal and undocumented together, add at least $36 billion per year net to the U.S. economy.

As Arizona’s experience confirms, the millions of undocumented workers also have not caused long-term unemployment to rise. Before 2008, undocumented foreigners made up 10% of Arizona’s 3-million-plus workforce. But unemployment was a mere 4%. In other words, they were filling a vacuum, not pushing natives aside.

Culturally, immigrants are not much different from natives either. They are overwhelmingly religious, highly entrepreneurial and largely family-oriented, with approximately half of all immigrants living with a spouse and child.

Perhaps all this explains why acculturation patterns are similar to those of previous waves of immigrants.

The immigration bill is by no means perfect, but it is better than previous reforms that created inflexible quota systems. The current measure will better respond to the needs of the economy, rather than the whims of bureaucrats and politicians.

That’s why immigration reform deserves House approval as well.