Even in the best case (for China), the Chinese had suzerain rights over Tibet according to the convention. That is not at all the same as Utah and the US. Also

Even in the best case (for China), the Chinese had suzerain rights over Tibet according to the convention. That is not at all the same as Utah and the US. Also, being an independent kingdom with antiquity Tibet has a right to challenge status quo based on history, which again is nothing like Utah/Mormons and the US since there was no Mormom state prior to it being a US territory.