It is not. There is no rationale given for a 180 degree turn from the doctrine which has been a part of Christian tradition for 2000 years.
<> You might want to consider E-mailing the Pope re the Death Penalty not being Doctrine. He appears to think differently. He wrote an Encyclical in which he cites the development of that Doctrine and it is also featured in the Universal Catechism. In the Encyclical he gives reasons why the Doctrine has developed. The Pope seems to think that is Doctrine.
What other Doctrines, in your opinion, can a Catholic reject and still be a "god Catholic?"<>