1) "...the net benefits to the U.S. economy from immigration, aside from the large gains to the immigrants themselves, are small...no more than a fraction of 1 percent." (Obviously, a gain is a gain, but 1 percent ain't much in the grand scheme of things.)
2) "...while immigration may have raised overall income slightly, many of the worst-off native-born Americans are hurt by immigration....U.S. high school dropouts would earn as much as 8 percent more if it weren't for Mexican immigration." (That's not good, obviously.)
3) "That's why it's intellectually dishonest to say, as President Bush does, that immigrants do 'jobs that Americans will not do.' The willingness of Americans to do a job depends on how much that job pays...." (I believe this is known as Econ 101 at Princeton, where Professor Krugman teaches.)
4) "America is a welfare state, even if our social safety net has more holes in it than it should ? and low-skill immigrants threaten to unravel that safety net." (This is an economic/social problem, obviously.)
5) Although "decency requires that we provide immigrants, once they're here, with essential health care, education for their children," the problem is that "low-skill immigrants don't pay enough taxes to cover the cost of the benefits they receive." (This one's an economic/social/moral problem.)
6) Although Mexican immigration, on balance, is only a "modest" problem economically, "immigration is becoming a major political issue," with large majorities of Americans favoring cuts in immigration numbers. (This one's a big-time political problem.)
7) In the end, "we'll need to reduce the inflow of low-skill immigrants. Mainly that means better controls on illegal immigration." (Why haven't the Republicans done this over the past 5 years since they've been in power? Oh, by the way, Jim Webb favors gaining control over our borders. How about George Allen, what's he done as a U.S. Senator?)
8) Having come to that conclusion, Krugman recoils from the "immoral," "harsh anti-immigration legislation passed by the House" ("legislation that would, among other things, make it a criminal act to provide an illegal immigrant with medical care"). And Krugman excoriates the Bush approach to immigration, which is "deeply un-American" and "clearly designed by and for corporate interests, who'd love to have a low-wage work force that couldn't vote." (A permanent underclass? In America? No thanks.)
9) Krugman concludes that we need a solution, but that "I'd rather see Congress fail to agree on anything this year than have it rush into ill-considered legislation that betrays our moral and democratic principles." (Exactly. Why doesn't Congress stick to legislation on things that don't betray our moral and democratic principles, like...oh...torture for example, or warrantless spying on Americans? Heh.)
In sum, Paul Krugman's editorial does a great job in thinking through - from a liberal perspective - the pros and cons of immigration, concluding that it's a small net economic benefit overall but a huge political and moral issue facing America. I would add that it's also an issue which sharply divides both political parties in this country, which is easy to demagogue, and which needs a lot more light and less heat. The question now is, what are we going to do about immigration in this country? And are we going to make the problem even worse by trying to fix it? I don't know about you, but I have very little faith that our current, Republican "leadership" will get this one right.