War isn't something good. No one benefit during or after war no matter the cause of the war. Imagine the resources and infrastructures destroy during the Russia and Ukrinre war recently.
That is not good for us peace-loving citizens, but for politicians, it is necessary to consolidate power as well as show strength. In war, the winner will be the beneficiary, they will have all they want if they win.
In war, the main beneficiaries are the arms sellers, and after the war ends, every country needs capital to rebuild the country, and the lenders benefit.
The wars in Ukraine and Russia are hurting the people of both countries and affecting everyone in the world, but there are always beneficiaries in it, and that's why they don't want it to end early.