@Apparently_Im_The_Grumpy_One Perhaps it might help if I share the thought process behind the answer of “religion”.
The first object to come to mind was guns. Taking them away wouldn’t take away the distrust and hatred that causes so much harm to others. What is something else?
In looking back through history, how many wars have been caused in the name of religion? How many deaths? How many countries outlaw homosexuality in the name of religion? Look at the struggle the US is having regarding the right to allow same sex couples to marry or even welcome them as a member of their congregation. How long have we been observing the Israeli-Palestinian conflict?
One could argue that there will always be issues between people that aren’t religious-based, and of course this is true. There would also be a great deal of good deeds and respect that still continue, and possibly more, if religions didn’t exist.