One reason is it helped promote exploration.
Another is communication was faster.
And people learned more about exploration.
The Russo-Japanese War showed the United States' growing role in world affairs after US President Theodore Roosevelt negotiated and convinced the two sides to sign a peace treaty to end the war. This showed that United States has a power and large influence in most country's decisions.
Rock n' Roll and Elvis Presley became popular in the 1950s through the rise of counterculture and young peoples desire for something new and rebellious. Elvis' music and rock'n roll more generally signified a shifting tide in American society amongst youth. Youth became interested in upsetting the status quo and listening and being involved in things that were once considered taboo like rock'n roll. Radio and TV helped to spread this music because it provided a medium for people to hear and learn of new artists and music styles quickly.
The U.S. attorney general stated that marijuana will be exempted from the Controlled Substances Act for it will become a medication to patients with serious diseases. He also stated that he will not tolerate those drug traffickers who will take advantage to the legalization of such substance.