Buddhism sounds good, but ultimately leads to the things I gave as examples because it teaches each man to find his own 'salvation." It also teaches that mankind is really nothing but a collection of molecules destined to reside for eternity with other molecules. {Secular Humanism=matter} This strips mankind of any intrinsic value. Hence, abortion, infanticide, etc.
Reincarnation & karmic teachings say you're destined to return. That leads to a disinclination on the part of society to alleviate suffering, injustice, etc., because the sufferer was obviously destined to suffer in his present life {fatalism/karma}, and he'll be returning anyhow, so why become involved?
"Theravada teaches that each man is responsible for their own this is reached by ones self-effort; "Be lamps unto yourselves. Be a refuge unto yourselves. Do not turn to any external refuge.... Work out your own salvation with diligence" (Mahaparinibbana-sutta 2.33; 6:10; from the Pali Canon)
In real terms this means that man is a moral sovereign unto himself, which is exactly the same reasoning employed by Secular Humanists. Buddhism and Secular Humanism are quite similar in their doctrinal beliefs, thus between Secular Humanism and New Age {neo-Buddhism/Hinduism/mysticism} America has been regressing into the ways of pantheism.......abortion, infanticide, child abandonment, euthanasia, sexualization of our culture, nature worship at the expense of mankind {Greens}, and so on. You said, "Many Christians engage in abortion." That is true. But they're doing that 'in spite' of and not "because of" Christian teachings. They are followers who have "fallen away" from Biblical teaching because they've become influenced by our Secular Humanist/New Age culture.
You become involved so you'll be reincarnated into a better situation. Sort of like heaven.