I am intrigued by the notion that Shin Buddhism (or Pure Land Buddhism) — and the Tea Ceremony — may be the outgrowth of Nestorian mission work (kerygma and eucharist respectively) at the Chinese court in the century or two preceding the Muslim expansion.
I am inclined to universalism, so I think that everyone will become a professing Christian ("every knee shall bow, every tongue proclaim...") in the
dénouement of the
Heilsgeschichte (or, if you will, when the Eschaton is finally immanentized
) sooner or later. I am not convinced that the river spoken of in faith that when one dies the Amida Buddha will ferry one's soul across the river to the Pure Land in the West is any less Jordan, in the salvific sense, than the river we cross after death with the assistance of angels enlisted through our faith in Jesus the Christ.
I think the Bible is replete with instances of God accounting one thing as another (the archetypical case being Abraham's faith as righteousness), whatever it takes to save.
As for the atheism of the Buddhists, it strikes me as not that different from the atheism of the Christians. (Remember, atheism was one of the principal charges brought against our forebears in the early Roman persecutions.)