it has affected directly the world economic, whenever a country sings an agreement with another one or applies a ban than it immediately affects the whole economy, usually in bad way.
The latest news that is happening is a trade war between China and America, whose impact will affect other countries. This happened because the tariff set by the US for Chinese products increased, and made it difficult for Chinese goods to enter America. China, of course, avenges America's treatment harshly, so it is feared that the impact will be felt globally because China and America are economic giants.