Speak for yourself.
There are plenty of peeps here who do not view polyamory as something we are, but just a way we choose to live. To us, it's a practice, an approach, a structure, not an identity or "wiring" (stupid term). The fact that you feel it is what you are only reflects how YOU feel about it, but you cannot speak for all.
In addition, even if one is the type who feels it is an identity and the way one is, doesn't automatically catapult one into multiple relationships. You can see yourself as a poly person and still live monogamously or have no relationships at all. There is a point where one chooses to enter into more than one relationship, or not, and everyone's path to that choice is different. I believe that is what the OP is asking about, not whether you see yourself as "wired" that way.
Thanks so much for all the responses to my original question. I've come back periodically to read them and have to say that this response from Nycindie hits closest to what I was trying to say. I've thought a lot about this and in the end I don't "identify" as poly, rather I have come to recognize that I have the capacity to love in a polyamorous way.
I was very fulfilled in my monogamous relationship for well over 20 years. I never felt like anything was missing and I never actually considered that I may even want an additional love relationship. But it happened. I fell hard for another person, it came to a point where it was absolutely undeniable, and now I'm in a very fulfilling polyamorous relationship. In that, perhaps, I didn't have a choice. Love happens, and when it does it is amazing and beautiful, and I wouldn't change a single thing about the experience I've had.
But, if the relationship ended tomorrow (which would be horrible!), I wouldn't go out and seek another partner because I "am" poly or even just because I know I have the "capacity" to love more than one. If it happened again that I fell for someone else, it would happen. But I wouldn't actually seek it. As I said, I was fulfilled in my mono relationship with my husband before, and I expect I would be fulfilled and happy in that relationship in the future as well. I like to think that even if I were single I would be fulfilled. I think in part my question came from having read a lot of posts from people who are single or in relationships already and were actively seeking new additional relationships. Nothing wrong with that at all. That is what they want and that is great for them. I guess I was just curious and trying to use the information to help me make sense of and process my own experience.
Yes, I know in my original post I talked about the relationship being hard and being work. In retrospect, those were probably the wrong words. It *is* work, but it is *good* work as I have learned so much about myself from doing it, and have grown personally in some incredible ways. But the reality is that I've had to face deeply rooted insecurities and fears and the process of doing that can be challenging, even if the ultimate outcome is good. So I guess that is what I meant by that.
I hope all that makes sense. This is all still a journey for me and I am still learning and growing from it, and my understanding of it all is still evolving.
Thanks again to everyone for the thoughtful responses.