There was a large desire for slaves because these slaves didn't need to be paid, as long as they were fed, they would be able to work for any amount of time for next to no cost at all.
Well, I'm not sure which war you're referencing. But, if it's WWI, they did it through war bonds and taxes. Mostly war bonds.
Explanation:
<h3>In the turmoil surrounding the unpopular Vietnam War, lowering the national voting age became a controversial topic. Responding to arguments that those old enough to be drafted for military service, should be able to exercise the right to vote, Congress lowered the voting age as part of the Voting Rights Act of 1970.Jul 1, 1971
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In theory with radio or Morse code light messages, they could coordinate attacks and such, probably with radio<span />