There may be nothing more disturbing than accidentally running into a broadcast of Lou Dobbs Tonight on CNN. But there I was at the gym last night, captive to Dobbs ranting about the 300,000 illegal aliens who were supposedly going to be stealing American jobs. (I wrote earlier about the faulty assumptions and outdated statistics that story relied on.)

Still, it got me wondering about what the economic impact really is of illegal immigration, and what the impact might be if advocates of comprehensive immigration reform got the path to legalization they’ve been advocating.

Among the helpful points in this thorough examination of the subject from The American Prospect is that the Internal Revenue Service estimates that undocumented immigrants contributed nearly $50 billion in federal taxes between 1996 and 2003.

The author’s main point, though, is that providing undocumented workers a path to legalization would ultimately have the effect of raising wages for everyone — it’s far harder to under-pay and otherwise exploit legal workers.

Perhaps most importantly, legal, tax-paying hard-working immigrants drive up demands for homes, cars, goods and services — and ultimately, that’s what we desperately need right now. The destitution or deportation of 11 million people within our borders, leading to more foreclosures and business failures, isn’t going to help anyone.

The claims by Dobbs and others, such as Fredrick County, Md. Sheriff Charles Jenkins, who claimed at a congressional hearing last week that the rise in crime in many communities “can be tied directly to the unchecked flow of illegal immigrants through our southern borders with Mexico,â€