How to Start a War
1) Declare that a country is an enemy, "dangerous". Although your country has nuclear weapons, declare the other country should not.
2) Starve and harm the other country economically with a blockade oil sales, etc.
3) Create difficulty in that country due to your blockade so that there is inflation and the people suffer.
4) When desperate enough, observe the other country strike back.
5) When the predictable action takes place (like the strike on Saudi Aramco) claim justification for war, whether or not you can validate the claim.
6. Employ more propaganda to get your population to demonize the "enemy" and justify war.
(We are getting pretty good at this)