One important fact you miss (and the author missed also). All US bonds are dollar denominated assets.
The dollar was hugely overvalued (and still is, but less), as a direct result of China (and others) buying all this debt. By the time we repay this debt, the dollar will be less overvalued. This means that China gave us a $1=100 yuan loan, and gets back $1=80 yuan (numbers strictly made up, interest neglected).
To push the analogy way too far, it's as if I bought stuff on a credit card, with payments due in AngryProfessorBucks (which I can print as many of as I want).
So in short, it's good for us, but sucks for China. We get cheap products now, and pay for it with low value currency later.
The dollar was hugely overvalued (and still is, but less), as a direct result of China (and others) buying all this debt. By the time we repay this debt, the dollar will be less overvalued. This means that China gave us a $1=100 yuan loan, and gets back $1=80 yuan (numbers strictly made up, interest neglected).
To push the analogy way too far, it's as if I bought stuff on a credit card, with payments due in AngryProfessorBucks (which I can print as many of as I want).
So in short, it's good for us, but sucks for China. We get cheap products now, and pay for it with low value currency later.