You can manipulate your current state based on an expected future. Doing something today in hope of a delayed reward is good, but a simpler mental relief may be enough. If a war was to start in 10 years, your actions today wouldn't matter. However, not stressing about it for 10 years will definitely leave you in better mental state. Expectations can't be disappointing when combined with a proper worldview. Tomorrow will always be nice because you will have the opportunity to live it.