The main issues of the immediate future are basic survival issues like food, water, and clean air. The melting of the world's glaciers is already leading to less fresh water in the rivers of the world.
The main cause of WW1 was the assassination of Archduke Franz Ferdinand.
It was the main cause
because it probably has alot of pollen,and pollen is usually the main cause of of sinuse swelling and other issues.
sometimes they have transportation issues but in my opinion the main cause is the use of the computers and cellphones until very late in the night
to make the world a better place
friendly fire
Commerce
Why world's population has increased rapidly in last hundred years and main problems will cause?
World War II was the main issue in Europe at the time.
George Washington
Most of the Arab nations cite the Israeli-Palestinian conflict as the main issue preventing them from signing peace accords with Israel, and having diplomatic relations. The Syrian-Israeli issue is with the Golan Heights, a mountain range between the countries, occupied by Israel in the six day war.