Why so little Christians in Japan?

Only one percent of the Japanese population is Christians.
We have 450 years' history of Christianity.
Missionaries came to Japan in mid 16th century.

Late 16th century was the period they made success having Christians in Japan
It is said that Spanish missionaries went teaching to upper class of the people including several loads.
Loads sent boys' mission to Rome.
They built a large scale church.

We go to services twice or three times a month near by Methodist church which has a history of
90 years. There are 3-40 people gathered. Mostly senior people.
Chistianity is understandable for me than Buddhism which most of Japanese are.

From the beginning of 17th to mid 19th century for almost 250 years Japan closed the country and Chistianity was prohibited.
But there were so called Hidden Christians in mostly western part of Japan even during the period.

After Meiji restoration in 1868, there were many Christian schools established.
Many people learnd there.

But why so little Christians?
I believe "Shinto" is a different existance and Shinto is not the reason of this phenomenon.

see, http://blogs.yahoo.co.jp/japaneseweapons some photos and English