While it's fun to think about grizzlies in New York and California and where ever, the reality is that grizzlies were most abundant in the Great Plains prior to the arrival of European settlers. They prefer open habitat, but the remnants of the original populations are in the mountains mostly because that's where they were the hardest to find and kill. So we've made a decision as a society (a decision many, many people disagree with) that we will allow them to continue to exist in the wildest areas of their former range. The reason for this is that most of the original habitat is now farm land, and we're not giving that back, but also because grizzlies truly are so prone to conflict with humans that human-caused mortality becomes a limiting factor for them wherever they have frequent contact with human population densities.
That's why British Columbia, which has 25% of the North American grizzly population, has a big zone of extirpated and threatened populations centered around their human population densities. So if BC with 25% of the total population can't recover bears along the border, it seems silly to believe that we can re-establish an isolated population in the Washington Cascades. Recovery of the Yellowstone population is confirming the conflict scenario, with conflicts increasing along with the population. It tells me that even the largest wild portion of the lower 48 (Yellowstone and Northern Rocky Mtns in general) can barely support a viable population without conflicts leading to human-caused mortality as a population limiting factor. The Cascades have nowhere near the habitat or food resources as Yellowstone, and a huge and dense human population surrounding it. Washington is the smallest western state with a population and population density second only to California. And those densely populated areas are what actually look good to a grizzly when it comes to habitat, not the steep, rocky, pecker-pole choked forests of the North Cascades.
Hopefully we can learn from our experiences with predator population recovery and re-introductions as we go. I understand the frustration of those who live in the Rockies and opposed these recovery efforts from the start, but lets not cut off our nose to spite our face, because in that case I'd say grizzly recover starts in the Bread Belt, along with bison, elk, prairie dogs and the whole suite of other predators to go with them.