Killing baby Hitler

I recently watched the movie Looper. It asks (essentially) whether we'd be willling to kill baby Hitler if we were able to travel back in time.

While browsing thru some reviews and commentaries online, I noticed some secularists argue for killing baby Hitler. But it's ironic how these secularists say stuff like they'd kill baby Hitler in a heartbeat in order to prevent the Holocaust, WWII, and other great evils, whereas on the topic of killing the Canaanites they'd hardly be so sanguine. How do these same secularists know Canaanite babies weren't each ticking time-bomb baby Hitlers, so to speak?

However, other secularists argue they would not kill baby Hitler. Here's a compelling reason that's been given:

Paradoxes abound.

By killing Hitler then the likelihood that you would never have been born to get on the time machine in the first place would be quite high, and in my case the chances of my parents ever meeting would have been remote.

To go back in time and kill Hitler would be to wipe out all those people alive today in which the war and its consequences were consistent with the appropriate sperm meeting the appropriate egg.

A large chunk of humanity, I'd guess.

Likewise:

If I did so I wouldn't be here to go back in time and do it.

My parents wouldn't have met if it hadn't been for WWII.

We are all the spawn of the misfortunes of yesteryear.