Critics of Senator Barack Obama make a strategic mistake when they talk about his "past associations." That just gives his many defenders in the media an opportunity to counter-attack against "guilt by association."

We all have associations, whether at the office, in our neighborhood or in various recreational activities. Most of us neither know nor care what our associates believe or say about politics.

Associations are very different from alliances. Allies are not just people who happen to be where you are or who happen to be doing the same things you do. You choose allies deliberately for a reason. The kind of allies you choose says something about you.

Jeremiah Wright, Father Michael Pfleger, William Ayers and Antoin Rezko are not just people who happened to be at the same place at the same time as Barack Obama. They are people with whom he chose to ally himself for years, and with some of whom some serious money changed hands.

Some gave political support, and some gave financial support, to Obama's election campaigns, and Obama in turn contributed either his own money or the taxpayers' money to some of them. That is a familiar political alliance— but an alliance is not just an "association" from being at the same place at the same time.

Obama could have allied himself with all sorts of other people. But, time and again, he allied himself with people who openly expressed their hatred of America. No amount of flags on his campaign platforms this election year can change that.

Unfortunately, all that most people know about Barack Obama is his own rhetoric and that of his critics. Moreover, some of his more irresponsible critics have made wild accusations— that he is not an American citizen or that he is a Muslim, for example.

All that such false charges do is discredit Obama's critics in general. Fortunately, there is a documented, factual account of what Barack Obama has actually been doing over the years, as distinguished from what he has been saying during this election campaign, in a new best-selling book.

That book is titled "The Case Against Barack Obama" by David Freddoso. He starts off in the introduction by repudiating those critics of Obama who "have been content merely to slander him— to claim falsely that he refuses to salute the U.S. flag or was sworn into office on a Koran, or that he was born in a foreign country."

This is a serious book with 35 pages of documentation in the back to support the things said in the main text. In other words, if you don't believe what the author says, he lets you know where you can go check it out.

Barack Obama's being the first serious black candidate for President of the United States is what most people consider remarkable but how he got there is at least equally surprising.

The story of Obama's political career is not a pretty story. He won his first political victory by being the only candidate on the ballot— after hiring someone skilled at disqualifying the signers of opposing candidates' petitions, on whatever technicality he could come up with.

Despite his words today about "change" and "cleaning up the mess in Washington," Obama was not on the side of reformers who were trying to change the status quo of corrupt, machine politics in Chicago and clean up the mess there. Obama came out in favor of the Daley machine and against reform candidates.

Senator Obama is running on an image that is directly the opposite of what he has been doing for two decades. His escapes from his past have been as remarkable as the great escapes of Houdini.

Why much of the public and the media have been so mesmerized by the words and the image of Obama, and so little interested in learning about the factual reality, was perhaps best explained by an official of the Democratic Party: "People don't come to Obama for what he's done, they come because of what they hope he can be."

David Freddoso's book should be read by those people who want to know what the facts are. But neither this book nor anything else is likely to change the minds of Obama's true believers, who have made up their minds and don't want to be confused by the facts.

To find out more about Thomas Sowell and read features by other Creators Syndicate columnists and cartoonists, visit the Creators Syndicate web page at www.creators.com. Thomas Sowell is a senior fellow at the Hoover Institution, Stanford University, Stanford, CA 94305. His Web site is www.tsowell.com.

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