I don't speak for all Kemetic recons, of course, but my own personal experience has been that Kemetic reconstructionism is not so much inspired by other Egypt-centered religious movements, but is rather one part of a larger reaction to the modern religious trend toward a cultural bricolage style of spirituality.
I began exploring Paganism through the religion of Wicca. Actually the term "NeoWicca" might be a bit more appropriate, because I was not an initiated member of a traditional coven- there weren't any in my area, and since I found out about the movement from books it was a while before I learned the significance of lineage or the changes which were causing factions to branch off within Wicca as a whole.
Still, I found my time there to be inspiring- and it was through Wicca that I first began to approach any Egyptian gods or goddesses. The books I was reading at the time were presenting the gods and goddesses of many different times and regions all together, and these wrote about the gods of various different pantheons as if They were interchangeable, all followed the same basic themes, and were worshipped in the same style. So at first, my personal pantheon was a combination of cultures- primarily Pan and Bast.
To make a long story short, after I'd had time to do quite a bit more reading I began to realize that Wicca was its own religion- not the preserved template of all Pre-Christian spirituality. And I began to realize that each of the deities belonged to a distinct culture; that each culture had its own ideals, values, and ettiquette; and it occured to me that learning about a deity's traditions would be an offering of respect and love equal to any of the fine offerings which I would have loved to have given but could not afford.
So I began to give my offering of study, devotion, and knowledge. I chose Egypt simply because by that point all of the gods I worshipped were of Egyptian origin- the others seemed to have packed up and moved on. The Egyptian conception of deity is in several ways very different from the Wiccan one- the first time I found a lunar god and a solar goddess, for example, that completely blew the Wiccan template of God and Goddess associations out of the water. It further impressed upon me the need to study the specific culture of my gods, to find out what other mistaken assumptions had been made. At about the same time I was distressed by the increasing tendency within the Wiccan religion to be unable to agree on its own identity. There was so much pressure to accept any and all innovation that I really couldn't figure out who we were anymore.
The day I realized that I rarely used any of my NeoPagan books any more, and that my religious library was becoming filled with Egyptology instead, I knew I'd crossed a line. That was when I became a reconstructionist. Strangely enough, at about the same time that I'd come to that realization, about half of my hometown's Pagan population confirmed that they had come to similar conclusions about themselves. They weren't all interested in ancient Egypt, but they had become reconstructionists. Since then, I've seen the recon movement growing fast.
So in my opinion, Kemetic reconstructionism would be more properly located within the reconstructionist movement than within a group of Egyptian-themed magical or religious orders. And that reconstructionist movement derives from a fundamental cleft in the Pagan family tree- with one branch growing toward a free-form and universalist style of spirituality, and the other growing toward a traditional and culturally focused style of spirituality. Recons are located firmly within that second branch, and share a deep reverence and joy in the depth and richness of the many cultural heritages of the different parts of the world. We also share a respect for the professions which are devoted to learning about and preserving those legacies, and have generally adopted many of the same measures which those professions use to ensure the integrity of their studies. That those of us here on this board happen to study ancient Egypt in this way is simply a matter of our own personal preferences. Otherwise, we may have ended up on the Ta Hiera SIG, or the Asatru SIG, or some other culturally based forum.
And now I must be off, or I will miss my train!
