It's mind-boggling that folks at both ends of Pennsylvania Avenue could spend so much time and energy over the last five years debating immigration reform, yet still manage to steer clear of some of the touchier issues involved.

Members of Congress were content to huddle around President Bush last week as he signed a bill calling for 700 miles of fencing on the U.S.-Mexican border. The photo-op was intended to fool us into thinking that something has been accomplished in the area of border security.

What was accomplished was very little. Even if lawmakers had come up with all the funding to pay for the fencing -- and they didn't -- barriers only squeeze more illegal immigrants through those parts of the border that aren't fenced off. In the 1990s, crackdowns in El Paso and San Diego sent millions of illegal immigrants to crossing points in the Arizona desert.

The country would have been better served by an honest discussion of matters indispensable to any meaningful debate of immigration policy:

-- Today's immigrants are not so different from those who came to America from Europe a century ago. The fact that the earlier wave came legally (there was no way to come illegally until the early 20th century, when Congress first took steps to limit immigration) didn't make them any more welcome at the time. Then, as now, the fear was that immigrants -- from Ireland or Italy -- wouldn't assimilate. And, of course, eventually they did.

-- Then, as now, racism and nativism were intrinsic parts of the discussion whether or not people were willing to admit it. How else does a nation of immigrants even begin to make the case that a new batch of immigrants is more menacing and harmful to society than previous batches unless you can argue that the new immigrants are somehow inferior to the old ones?

-- Illegal immigration is a self-inflicted wound. Local municipalities complain about the cost of providing education, health care and other services to illegal immigrants and their children. But they should at least be honest about the benefit their communities derive from the availability of cheap labor, which, in many cases, keeps local economies humming in cities such as Phoenix, Dallas or Las Vegas.

-- Despite popular misconceptions, Hispanic immigrants and their children are indeed assimilating just as they have been for generations. According to recent studies, they learn English and lose Spanish, adopt the common culture and shared values, and become Americanized. Fortune 500 companies may still rely on Spanish ad campaigns and other forms of ethnic marketing to sell their products, but, increasingly, Hispanics speak English.

-- Our dependence on illegal immigrant labor, combined with the fact that -- according to research such as a September 2006 study by the Center for Immigration Studies -- most of the job displacement has occurred with younger workers, confirms what Americans suspected: that, along with modern-day advances, our native-born young people don't have the work ethic they did a generation or two ago and that illegal immigrants pick up the slack.

-- Despite talk about the impact that illegal immigration has on working-class Americans, the untold story is the effect that illegal immigrants have on those in the middle and upper class. Illegal immigrants let Americans fulfill their earning potential while making accessible to the middle class what used to be considered luxuries reserved for the wealthy, such as nannies and maids.

-- And lastly, you can't control illegal immigration without cracking down on employers and you can't crack down on employers without going after the "casual user." The problem isn't just farms and construction firms. It's the suburban housewife, nurse or teacher who hires someone to help maintain the household -- without concern for whether the worker is in the country legally.

A lot of this is tough to hear, and so it's no wonder our lawmakers were none too anxious to broach these subjects with voters. So instead the politicians went for the low-hanging fruit and passed a bill calling for a fence.

If the barrier is ever actually built -- and don't hold your breath -- we should hang signs every 10 miles that read: "Congress talked itself silly for five years debating immigration reform and all we got was this dumb fence."