Depends on the problem. We had our own war that started over an assassination, rapid militarization, and secret alliances. And all of people in the nations involved initially celebrated the declaration of war because essentially, people saw it as a competition of which nations were better than the other nations.
That’s right, I’m talking about The Great War (World War I).
Former empire Austria-Hungary declared war on Serbia because a Serbian national assassinated the Archduke.
Russia declares war on Austria Hungary because its allies with Serbia.
Germany declares war on Russia because its allies with Austria-Hungary.
France declares war on Germany because it’s Allie’s with Russia and Germany took the territories Alsace and Lorraine in a previous war.
The Ottoman Empire declares war because they want some of Russia’s territory.
The UK declares war on Germany after they violate Belgium’s neutrality.
Bulgaria jumps in because they want a larger share of the territory Macedonia and declares war on Serbia.
And it goes on. We’ve started wars over similar reasons presented in the books.