Iron Golems summoned through commands try to attack but can't deal damage to players

What I expected to happen was...:
The player should be thrown up into the air and hurt

What actually happened was...:
The iron golem continuously threw it's arms up but couldn't do anything

Steps to Reproduce:
1. Type /summon minecraft:iron_golem
2. Go into survival mode
3. Punch Iron Golem
4. Let it try to attack