SCOTT OLSON / GETTY IMAGES

Young men scale a border fence in Agua Pietra, Mexico.

Old fears over new faces

U.S. immigration is a long-running drama with a regularly changing cast — from the Irish and Italians of yesteryear to the Mexicans and other Latinos of today. But one thing has remained constant: the concerns voiced over the influx of newcomers.

• Immigration legislation since 1790
• Immigration waves in Washington state
• Tracking more than a century of immigration

Millions live among us: Do they hurt or help?

The number of illegal immigrants in the United States has grown by up to 500,000 a year recently, officials say, but experts can't agree on the total number now here. There's also continuing debate on the net impact on this country.

• Immigrants in the U.S., legally and illegally

Dispatches from the frontier

Though only half as long as the boundary with Canada, the U.S. border with Mexico is marked by a combination of conflict and cooperation, of mounting tensions and shared aspirations.

• World-class walls
• Northern vs. southern border

U.S. residency: going for the green

Family ties, certain jobs and even the luck of the draw can ease the way of those wanting to live permanently in the United States. But those paths usually are blocked for immigrants who already have entered the country illegally.

• Citizenship: Latinos less likely to naturalize
• Take the U.S. citizenship test

Many proposals, no consensus

Send in the military? Set up guest-worker programs? Crack down on companies that hire illegal immigrants? Build more fences? Every suggestion stirs up opposition, much of it citing related failures of the past.

• Sealing the border
• Workplace enforcement
• Guest-worker programs
• Military presence
• Fence design, proposed locations
• Political pull bends immigration policy

Building wealth, not walls

Rather than concentrating on border enforcement, some say the U.S. should follow the lead of Europe, where well-to-do countries subsidize poorer ones. Others say Mexico must change its ways to provide its people more opportunities at home. The price of living next to a country with a fraction of your wealth is a lot of immigration, wanted or not.

• South-of-the-border retirees could aid the whole region