What MOST led to such high tension during the cold war? (communism/containment, space race, cuban missile crisis, etc.) How could this issue have been resolved before becoming a bigger problem?

Communism

Because US and Soviet Union wanted world dominance or a capitalist world (US) or a communist world (Soviet Union).

The Cold War began shortly after World War II, as the United States and the Soviet Union contested political, economic and military hegemony in the world. A direct armed conflict would mean the end of both countries and, probably, of life on planet Earth.

This could have been avoided if no country wanted to rule the world.

genetics is the study of how dna works, the methodologies defining the new recent technologies allow scientist to have a panoramic view of the entire dna landscape, especially how genomes interact with their environment, including off course, factors outside their organisms.

thus is very possible the existence of both scenarios, where populations of isolated individuals have different genetic traits, and share traits related to genetic mutation, due rats can easily travel overseas using human transport channels. so scientists could get a vast number of data, including human interaction, evolution of rodents, health development, spread of infections, development of new organisms, how genomes evolve in different environments and so on.

the government paid religious orders to provide basic education to native american children on reservations. in the late 19th and early 20th centuries, the bureau of indian affairs (bia) founded additional boarding schools based on the assimilation model of the off-reservation carlisle indian industrial school.