1- Jim Crow laws are laws that were made to legalize racial segregation
2- Changes in the constitution allowed African Americans freedom but after reconstruction laws were made to limit their freedom
3- Their lives changed in that they were no longer slaves and forced to labor but what stayed the same was the fact that they were still under oppression
4-Booker T. Washington proposed that economic progress would prove whites African Americans value and W.E.B Dubois believed you had to educate and fight.
Think about that expression -- crossroads of culture. The early West was something of a plethora of human beings, with people of all breeds and flavors a) travelling, such as the Mormon (Latter-day Saint) pioneers, b) going for gold (Gold Rush), c) running a business, etc. Another factor to consider is that the pioneers (the Mormons) had their numbers bolstered by people from England, Ireland, Scotland, throughout the US and other places, in consequence of missionary efforts by the Latter-Day Saint Church, and in response to the call of their prophet to "gather to Zion." With that amalgamation of people it's not hard to see why, at least in the early settlements, it's called a "crossroads of culture," due to the hundreds of types of variety present. Of course, other immigrants and families moved to the west other than the Mormons. I don't mean to imply the Mormons were alone in their endeavor.
The Soviets were setting up nuclear missiles in Cuba. This meant that they were now able in theory to launch a nuclear missile directly at large parts of the USA and it was therefore viewed as a threat by the USA. I hope that helps.
