I'm not 100% sure but it could be: Voluntary Exchange takes place between buyers and sellers:
(btw I copied and pasted from the question so I didn't take any content :D)
the senate represents the entires state
Union Flag (1606–1801), in which are combined the white-on-blue Cross of St. Andrew (for Scotland) and the red-on-white Cross of St. George (for England). The Union Jack is the most important of all British flags and is flown by representatives of the United Kingdom all the world over.
Answer:
1) New and revolucionary tactics and weapons (european powers use the inspirations in WWI)
2) Number of fallen remains far higher than in any other american war before or after
3) That is was war to prevent seccesion of Southern states and breaking of USA
The answer should either be Sanction or Embargo.
