British churches now send more missionaries to France than to any other country in the world, a church study reported last week. For centuries, Christian missionaries concentrated mostly on converting Africans and Asians. But now they are turning their focus to Europeans, who have been growing increasingly secular in outlook. France, despite its wealth of cathedrals, has seen its number of practicing Catholics drop dramatically in recent years, and the country has hardly any Protestants. Practicing Muslims in France outnumber practicing evangelical Christians by 12 to one.