President Obama is scheduled to meet with the Dalai Lama today in the White House. The Chinese are extremely upset and have even hinted they will try to injure the American economy if the meeting occurs.

Why is Beijing so angered by this event? After all, previous American presidents have welcomed His Holiness. There are many reasons, and most of them are beyond our control. There is one, however, that is not.

In October, Mr. Obama refused to see the Tibetan leader when he traveled to Washington. The explanation was that the president wanted to smooth relations with China before his summit in Beijing, which was scheduled for November. In the Chinese capital, however, Mr. Obama told Hu Jintao, his Chinese counterpart, that he would go ahead and see the Dalai Lama later.

The Chinese must have sensed that Obama, by shunning the Nobel laureate in October, felt he was playing a weak hand. Otherwise, why would the American leader try to accommodate them? So Beijing pressed what it saw as its advantage. It is no coincidence that, at the November summit, the Chinese were intransigent on almost every issue and that Premier Wen Jiabao snubbed Mr. Obama at the climate-change conference in Copenhagen in December.

So Beijing thought that by harsh words this month, Obama would back down this time as well. The Chinese believe the United States is in terminal decline, and unfortunately that perception is reinforced when the American leader acts as if he agrees.

Gordon G. Chang is the author of "The Coming Collapse of China." He writes a weekly column at Forbes.com.