What rider concluded that european society was on the decline after world war ii

Oswald Spengler concluded that European society was on the decline after World War 1. because Oswald Spengler was a "German historian and philosopher"

Explanation:

i smell fart because the kid next to me smells bad

a. because the u.s. was the leading with the most technology, economy, etc. also was teamed with other allies witch boosted the economy and materials to improve technology and use it.