What made Native American peoples vulnerable to conquest by European adventurers?

Question 1:
What made Native American peoples vulnerable to conquest by European adventurers?
*with one source/citaion

Question 2:
Why was the Constitution a controversial document even as it was being written?
*with one source/citaion

Question 3:
Why did women’s issues suddenly become so prominent in American culture?
*with one source/citaion

Question 4:
n 1860, the institution of slavery was firmly entrenched in the United States; by 1865, it was dead. How did this happen? How did Union policy toward slavery and enslaved people change over the course of the war? Why did it change?
*with one source/citaion

Be sure to include as much information as possible to support your answer. Each answer should be 3-5 paragraphs in length. Be sure to cite your sources.