Anyone who knows the least bit about history (and one suspects that President Bush must have slept through his history classes at Yale), knows that for anyone occupying Afghanistan, the Khyber Pass is the key. Pakistani militants understand this, and are attempting to make resupply through the pass difficult, if not impossible. From the article:
NATO and U.S. officials have said that losses along the supply route are not affecting their operations in Afghanistan. Still, NATO is seeking to open alternative routes through Central Asia.
I don’t believe that for a minute. These attacks are affecting resupply, NATO and the US obviously can’t admit it for strategic reasons.