Majority of the estimated 16 million Chinese Catholics are "underground," although not literally,
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because they are not part of, or refuse to join, the Chinese Patriotic Association, the "official" organization recognized by the Communist government of China.
Thus, the continued persecution of Catholics loyal to Rome.
They are in the "open" most of the time enabling the local and foreign media to record their activities. Remember the beating of the Chinese nuns recently which was recorded mostly by the foreign media and circulated throughout the world?
However, Rome does not distinguish between the two and, in fact, 3 of the invited Chinese bishops to the recent World Synod on the Eucharist were bishops affiliated with the CPA but, nonetheless, the Communist Chinese government also blocked their travel to Rome.
Further, the 2 dozens or so Chinese seminarians who had an audience twice with Pope Benedict XVI before going on to attend the 2005 World Youth Day in Cologne were seminarians of both the "underground" and the CPA.
As Westerners often say: the "inscrutable" Chinese!
Amado