Because of problems like these, and the general trustworthiness of BGP4, the re-evaluation of peer requirements have been all but forced upon major backbone providers. Just imagine if you were UUNET, (or Sprint, or MCI, or anyone with heavy backbone traffic in general) and one of your BGP4 routing partners black holed part of your backbone...
Refusing to peer with other providers doesn't prevent any of those things, it simply makes it harder to get the right people talking to each other. If you have a peering agreement with the other provider, you have a communications channel to resolve problems. If you don't talk to the other provider ahead of time, then when they blackhole your backbone, you have no clue who to call at the other provider to get it fixed. Besides, most of the major providers previously based the bulk of their peering 'requirements' on how many DS3s you had. Now most 'major' providers seem to have gone cold turkey. MCI, Sprint, and UUNET told me they won't peer with *anyone* new. -- Sean Donelan, Data Research Associates, Inc, St. Louis, MO Affiliation given for identification not representation