Answer:
In general, the events leading to a war are simple. First, two countries get into a conflict, this is the spark that can trigger fights, and eventually a war. Second, Surveillance begins in each country, normally done by the opposing country to see where their opponent's weak points are. Then begins the threatening. If neither countries comply with each others terms, then a war begins. Take for example Russia and Ukraine.
The domino effect, in simple terms, is the effect on which one event has on others. This means that one event triggers a chain of other events, eventually leading to something happening.
Explanation:
I hope this helps :)
