James: Even if there evolves a mixed-Buddhist lineage in America from the cauldron of melting Buddhist ideas; there will still be a place for the traditional lineages. Zen, Theravada, Tibetan, Pure Land, and the others will always have a strong, undiluted foot-hold here in America. However, it is inevitable as the Rinpoche describes for a specific American Buddhist tradition to form. No one can say what it will look like exactly but the melting is well underway.
I personally am happy right where I am in the Zen tradition of Thich Nhat Hanh. However, I would have to kindly disagree with the notion that Buddhism in Asia is "pure." Buddhism in Vietnam for example is a blend of Mahayana, Theravada and Pure Land Buddhism. Yet, not many people attack it as a bastardization of Buddhism as some say of Buddhism in America.
Culture wise, Tibetan Buddhism is rather particular to Tibet, Nepal and Bhutan. Their cultural traditions are very different from say the traditions of practice in Thailand or Japan for example. Yet, not many say they are a watered down mess of Buddhist ideas. All I am saying is that Buddhism is fluid and subject to change and adjustments like any other phenomena in this ever evolving life-span. Personally, I keep practicing my Soto Zen lineage but delight in the proliferation of ideas merging together in the cauldron of change.
I must admit that It is a bit odd to me that the people who oppose a mixing of traditions to form a unique "American Buddhism" are so resistant to change when Buddha taught that it is inevitable. Why would Buddhism be immune to it? And, why assume that change must be "bad" or "less than" other forms of Buddhism because it's adapting to a new culture -- American culture? Perhaps the traditionalists need to probe their discomfort with such a change and meditate on why it bothers them so much. There is plenty of room for everyone, and not everyone walks the exact same path in Buddhism -- even within the same lineage or tradition. Including the older, established ones such as in Theravada. Even within Theravada (which is arguably the tradition that sticks to uniformity the most) has it's variations.
We all must remember that change isn't necessarily always "bad." That said, an "American Buddhism" won't be for everyone and that's not just fine, it's the way things have to be in a complex, diverse, ever-changing world. If it adheres to the three jewels, the four noble truths, and the eightfold path while teaching compassion, emptiness and the other biggies in Buddhism then I welcome it.
~Peace to all beings~