It's a great day for Boeing (NYSE: BA) investors, as reports of a massive 200-plane, $19 billion export deal to China begin filtering out of Washington. It's a great day except for one thing: It isn't really all that great.

The deal in question -- the one getting all the press -- is part of $45 billion in export agreements involving American manufacturers Boeing and Alcoa (NYSE: AA), General Electric (NYSE: GE), Honeywell (NYSE: HON), Cummins (NYSE: CMI), and Caterpillar (NYSE: CAT) -- all trumpeted on the first day of Chinese President Hu Jintao's visit to the U.S. According to Contract-Signer-in-Chief Obama, these deals are "good for America. ... From machinery to software, from aviation to agriculture, these deals will support some 235,000 American jobs -- and that includes many manufacturing jobs."

All of which is true, but very little of which is new. You see, the subtext behind this week's announcements -- and the reason Boeing's stock was going down this morning instead of up -- is that most of these contracts were already signed long before Obama and Hu sat down to tea yesterday. As The Wall Street Journal notes in this morning's edition, "many of the agreements, including China's deal to buy $19 billion of airplanes from Boeing Co., have been previously announced; the report of Chinese approval was ... a flourish to bolster Mr. Obama's message that expanded trade with China can create U.S. jobs."

The operative word in that sentence, unless I miss my guess, would be: including. As in Boeing's not the only recipient of a puff press release from the White House today. So if you're a shareholder in Alcoa, Caterpillar -- any of the companies named above -- you'll want to check old press releases carefully before buying into the enthusiasm about this week's "news." Chances are it's not news at all, and the contracts in question are already in your stock's backlog.

No news isn't good news
Now don't get me wrong. I'm not saying trade with China is bad. Far from it. I'd love to hear that the president succeeded in helping American companies win more business from Chinese customers. But the plain fact of the matter is that he didn't, or at least not $45 billion worth. And that's why the stocks are taking a hit.

Fool contributor Rich Smith does not own shares of, nor is he short, any company named above. The Motley Fool has a disclosure policy.

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