WARS...
Easy. The reason is for sake of democracy and communist.
Western mainly US try to establish their ideology of democracy meanwhile the Russian and Chinese to spread their communism.
They will use anything includes by force IF necessary.
So now, they are fighting in Syria to control the gov.
For the Arab world, they go to wars simply because they dislike Jews. Its in their blood since before Moses.
The Turks are going to war to eliminate Kurds, like the eliminate the Armenian before.
And for North Korea, simply because they all stupid.