First Comparison:
WW1 and WW2 were both wars which involved darn near everyone to fight.
Both were fought mainly in the European theatre.
WW2 Asian countries were fighting each other.
Both times, Germany lost...
WW1 had trench warfare
WW2 had much close quarters.
USA entered... Reluctantly both times... Mainly for the other sides stupidity of. attacking the USA...
WW1 (in my opinion) is worse. Imagine that... Millions of men sent over a trench to fight an enemy they can't see. The enemy lying safely in trenches waiting to mow them down. For what... Only a mere kilometer of territory? Then Germany's punishment. Was unnecessarily harsh. This led to WW2.
Alt. WW2 (In other opinions) Think of the atrocities... The Holocaust. People sent to their deaths like animals... Don't forget about Unit 731. Asian Holocaust. The Nuclear bombs were made. The results were awe-inspiring... But at the same time... Terrifying....