I'm either wrong, or it's blindingly obvious, so not much discussed, but it seems like we could have had a drastically different internet that was more peer-to-peer in nature if we had started with something closer to IPv6, even just in terms of a larger address space. Like, the limited address space forced us into extensive use of local / site address spaces that required translation to access the wider internet. The need for translation, in turn, made network protocols that directly addressed one personal computer from another more difficult to implement.
Then again, with something like BitTorrent or ED2K, you can set up port-NAT, so it's not all that difficult really: a few extra user interface elements on the respective clients. Maybe it's ultimately more of a cultural thing. The lay person may not see the architectural short-falls of the intermediaries in our communications, or maybe they think the benefits outweigh the risks. Maybe the peer-to-peer tools just need to be better advertised.
