Pride or shame ?
American society in 1880-1920
As the peoples interests became more and more important overall parties begin to rise to appease those needs . The populist movement being among the first of these two arise in the 1890s and the progressive movement arising in the early 1900s. The populist movement was created by farmers that felt that they were being treated unfairly by banks machinery manufacturers and railroads . This movement was made because of the need for a voice in the government representing the common man .
Another political movement rose called the progressives , this group was made up of more urban people in the middle class that believed in a less lazzieh faire approach and believe that the government should be more involved in corporations and setting their boundaries.
Not so much a specific group, muckrakers began to arise in this era. These muckrakers were a kind of vigilante behind a pen, exploiting harsh conditions of jobs and corruption .
When the public would learn about the horrible things that were going on around them, reforms and movements would arise to counteract them and to push the government to do something about them.
There's more information about these reforms at http://www.westga.edu/~hgoodson/Politics%20and%20Reform.htm
Opportunity: the false hope
The newcomers , outcasted and hated , began to form unions such as the Jewish labor movement "yiddisher arbeter bund". Cultures like these became densely populated into smaller areas often next to each other to where they mixed.
In 1900 the workmen's circle is made to help Yiddish culture and work unions.
And politics around 1913 the anti defamation league was created in response to "anti Semitic tension " because of Leo Frank's unfair charge of murder.
Along with benefits though , the city dwellers suffered under political machines; members of political parties that were in charge of advertising their policies in cities. These political machines often bullied and pestered the local civilians to vote for their campaign.
Another cultural change was the way we built things. This was because of the growing steel, oil and mining industries.
WWII and imperialism
When Germany grew to be a technological power they were also running out of money. Soon an Austrian immigrant by the name of Adolf Hitler rose to power. During his reign, however inhumane, Germany gained power by using gruesome weapons like the flamethrower and artillery.