Bush Owns Investments He Said Were Worthless

Daniel Gross points out this interesting note from an Associated Press piece on President Bush's personal finances:

"The president reported having at least $4.95 million in Treasury notes."

This is the same President who essentially said Treasury notes were just worthless IOUs, sparking outrage.

If he really believed these Treasury notes were worthless (and wasn't just saying that to scare Americans), why would he choose to own them as personal investments?