Almost a thousand years ago, the “Ad abolendam” was issued to confront any number of heresies that plagued Europe. Today, however, a different approach should be considered, and a Holy Order tasked with a mission of education, to begin in the Americas and to continue throughout the world.
The concept is that many of the faithful have been confused and led astray by the secular world. The powerful enticements of materialism, philosophies, sexual excess, and dehumanism have lured them from the teachings of the church.
The sad fact is that many who call themselves Catholic have long been outside of the faith entirely. When summoned to return they will not, and despise the teachings of the church. So such a program of education is as much to divorce such people from any nominal embrace of the church, as it is to redeem those whose only failure is having been led astray.
That this be done by a Holy Order is so that the sheer number of teachers may meet with each and every person who number themselves among the Catholics, that each may have their say of their beliefs, and be taught if in variance.
Then, if the refuse the teachings and are stubborn, they will know that they are no longer Catholic. But if their beliefs are true, or they are willing to change to embrace the truth, they will once again be returned to the path.
I would say that it should start in Europe, but much of it is beyond hope, there is still hope in America (if Evangelicalism can thrive here, the Church can too).