The Treaty of Paris was signed by the U.S and Spain. After the treaty was ratified, the U.S became an imperial power. The U.S gained Puerto Rico, Guam, and the Philippines from the treaty.
A proposed wage cut of amalgamated association iron and steel workers
The reconstruction period had generally good ideas which were exploited by bad people and who turned it all upside down. The idea of reconstruction was to integrate African-Americans into the society and protect their rights and enable them to educate themselves and become sophisticated and emancipated members of the society.
During the gilded age, the focus switched form social to economic reforms and because of this the reconstruction ended and many southern states reverted to their original racist ways. This is why it's called the gilded age, it only looked like everything was great but it was bad at its core, like gilded items which only look gold.
The political, economic, and diplomatic crises of the 1780s played a great role in shaping the Constitution because they proved that the United States needed a much stronger central government that could tax freely and engage with other countries.