The answer behind your question is that Ecumenicalism is another head of the globalist hydra, and it has been decades in the making.
The thinking goes, "We want a one-world government, but religion is a problem since we recognise that we cannot get rid of religion. Therefore we must also have a one-world religion aligned with our goals."
It's purely geo-political and the Abrahamic religions in particular have each been targeted - Vatican II, Compassionate Imams, Chrislam, etc