Viewed in retrospect, Nidal Hasan's life becomes a trail of evidence leading to an inevitable end.

Domestically, Obama inherited an economic catastrophe. Dealing with the wreckage required a large expenditure of public funds that increased a deficit already bloated by President Bush's decision to fight two wars and to cut taxes at the same time. Bush's defenders, preferring to divert attention from this period of irresponsibility, act as if the world began on Jan. 20, 2009, by way of saddling Obama with the blame for everything that now ails us. But the previous eight years cannot be wished away.

A corollary of Murphy's Law ("If something can go wrong, it will") is: "Things are worse than they can possibly be." Energy Secretary Steven Chu, an atomic physicist, seems to embrace that corollary but ignores Gregg Easterbrook's "Law of Doomsaying": Predict catastrophe no sooner than five years hence but no later than 10 years away, soon enough to terrify but distant enough that people will forget if you are wrong.

Chu recently told the Los Angeles Times that global warming might melt 90 percent of California's snowpack, which stores much of the water needed for agriculture. This, Chu said, would mean "no more agriculture in California," the nation's leading food producer. Chu added: "I don't actually see how they can keep their cities going."

No more lettuce or Los Angeles? Chu likes predictions, so here is another: Nine decades hence, our great-great-grandchildren will add the disappearance of California artichokes to the list of predicted planetary calamities that did not happen. Global cooling recently joined that lengthening list.

In the 1970s, "a major cooling of the planet" was "widely considered inevitable" because it was "well established" that the Northern Hemisphere's climate "has been getting cooler since about 1950" (New York Times, May 21, 1975). Although some disputed that the "cooling trend" could result in "a return to another ice age" (the Times, Sept. 14, 1975), others anticipated "a full-blown 10,000-year ice age" involving "extensive Northern Hemisphere glaciation" (Science News, March 1, 1975, and Science magazine, Dec. 10, 1976, respectively). The "continued rapid cooling of the Earth" (Global Ecology, 1971) meant that "a new ice age must now stand alongside nuclear war as a likely source of wholesale death and misery" (International Wildlife, July 1975). "The world's climatologists are agreed" that we must "prepare for the next ice age" (Science Digest, February 1973). Because of "ominous signs" that "the Earth's climate seems to be cooling down," meteorologists were "almost unanimous" that "the trend will reduce agricultural productivity for the rest of the century," perhaps triggering catastrophic famines (Newsweek cover story, "The Cooling World," April 28, 1975). Armadillos were fleeing south from Nebraska, heat-seeking snails were retreating from Central European forests, the North Atlantic was "cooling down about as fast as an ocean can cool," glaciers had "begun to advance" and "growing seasons in England and Scandinavia are getting shorter" (Christian Science Monitor, Aug. 27, 1974).

Speaking of experts, in 1980 Paul Ehrlich, a Stanford scientist and environmental Cassandra who predicted calamitous food shortages by 1990, accepted a bet with economist Julian Simon. When Ehrlich predicted the imminent exhaustion of many nonrenewable natural resources, Simon challenged him: Pick a "basket" of any five such commodities, and I will wager that in a decade the price of the basket will decline, indicating decreased scarcity. Ehrlich picked five metals -- chrome, copper, nickel, tin and tungsten -- that he predicted would become more expensive. Not only did the price of the basket decline, the price of all five declined.

An expert Ehrlich consulted in picking the five was John Holdren, who today is President Obama's science adviser.

As global levels of sea ice declined last year, many experts said this was evidence of man-made global warming. Since September, however, the increase in sea ice has been the fastest change, either up or down, since 1979, when satellite record-keeping began. According to the University of Illinois' Arctic Climate Research Center, global sea ice levels now equal those of 1979.

Real calamities take our minds off hypothetical ones. Besides, according to the U.N. World Meteorological Organization, there has been no recorded global warming for more than a decade, or one-third of the span since the global cooling scare.

On December 26, two days after Nigerian Omar Abdulmutallab allegedly attempted to use underwear packed with plastic explosives to blow up the Amsterdam-to-Detroit flight he was on, and as it became clear internally that the Administration had suffered perhaps its most embarrassing failure in the area of national security, senior Obama White House aides, including chief of staff Rahm Emanuel, David Axelrod and new White House counsel Robert Bauer, ordered staff to begin researching similar breakdowns -- if any -- from the Bush Administration.

How Wikipedia's green doctor rewrote 5,428 climate articles.

Solomon draws attention to the online labors of one William M. Connolley, a Green Party activist and software engineer in Britain. Starting in February 2003, Connolley set to work on the Wikipedia site.　 I continue with a two-paragraph direct quote from Mr. Solomon's article:

[Connolley] rewrote Wikipedia's articles on global warming, on the greenhouse effect, on the instrumental temperature record, on the urban heat island, on climate models, on global cooling. On Feb. 14, he began to erase the Little Ice Age; on Aug. 11, the Medieval Warm Period. In October, he turned his attention to the hockey stick graph. He rewrote articles on the politics of global warming and on the scientists who were skeptical of the band [of climatologist activists]. Richard Lindzen and Fred Singer, two of the world's most distinguished climate scientists, were among his early targets, followed by others that the band [of activists] especially hated, such as Willie Soon and Sallie Baliunas of the Harvard-Smithsonian Center for Astrophysics, authorities on the Medieval Warm Period.

All told, Connolley created or rewrote 5,428 unique Wikipedia articles. His control over Wikipedia was greater still, however, through the role he obtained at Wikipedia as a website administrator, which allowed him to act with virtual impunity. When Connolley didn't like the subject of a certain article, he removed it -- more than 500 articles of various descriptions disappeared at his hand. When he disapproved of the arguments that others were making, he often had them barred -- over 2,000 Wikipedia contributors who ran afoul of him found themselves blocked from making further contributions. Acolytes whose writing conformed to Connolley's global warming views, in contrast, were rewarded with Wikipedia's blessings. In these ways, Connolley turned Wikipedia into the missionary wing of the global warming movement. ....

Online replies to this article included the following, appearing about 24 hours after Solomon's article went on line:

Recently, the Wikipedia Arbitration Committee determined that "William M. Connolley has, on a number of occasions misused his administrator tools by acting while involved" and, as a consequence, "William M. Connolley's administrative privileges are revoked."

How do Connolley and his co-conspirators exercise control? Take Wikipedia's page for Medieval Warm Period, as an example. In the three days following my column's appearance, this page alone was changed some 50 times in battles between Connolley's crew and those who want a fair presentation of history.