The main barrier a belief in God presents to the designs of the Left is that a belief in God elevates Him above the state. Leftists cannot abide that. The state is their church. Ever since Nietzsche wrote "God is dead", the Left has been busy inserting the state into that (according to them) vacant position. All the horrors of the 20th century are the fruit of it. As the article points out, the Left will break any number of eggs in pursuit of its omelette.
This contest of visions really is as old as mankind itself. The Christian position is that man is a fallen being, stained with original sin. Without God's salvation, man is hopelessly lost. The secular Left rejects this, of course. On the contrary, they believe man and his societies are perfectible through the application of "scientific socialism". The difference in visions cannot be overstated. The theistic (primarily Christian) vision acknowledges man as an imperfect being, which makes it inherently aware that an earthly pursuit of utopia is doomed to failure. The secular Left believes, through its enlightened ministration, that all the power and knowledge ascribed to God can be theirs. You can virtually see the serpent whispering into their ears, enticing them to partake of the fruit.
So if you ask me, that is the distilled difference between these two competing visions. Ours is the view that man is an inherently sinful being, and the best we can do on the earthly plane is try and mitigate our sinful nature through a respect for life, liberty, and property (happiness). Theirs is the view that any social ill real or imagined can be fixed by turning over control to them. Both of these visions already have an established track record, and it continues to mystify me that there is even an argument to be had.
