There is a common historical myth among Americans that the Alaska Purchase in 1867 was deeply unpopular -- that Americans didn't see any value in it and ridiculed it as "Seward's Folly" and "Seward's Icebox". But in reality there was widespread support for the purchase. Most of the newspaper reporting at the time was positive or at least neutral, and the treaty easily passed the Senate.
There were three main reasons for American support for the Alaska Purchase:
1. Americans and Russians did in fact know (contrary to the modern myth) that Alaska was rich in natural resources.
2. Many Americans believed that control of Alaska would make it easier to trade with Asia. (Americans had been trading with Asia since colonial times.)
3. Most Americans were in favor of annexing the British colonies north of the U.S. (what later became Canada), and they saw the acquisition of Alaska as furthering that goal.
One point I didn't make in the video but is worth noting:
The Senate passed the Alaska Purchase treaty 37-2. Some modern sources erroneously claim that the purchase "barely passed by one vote". Not true. The Constitution says the Senate ratifies a treaty with two-thirds of those voting, not two-thirds of all members. So the treaty got 95% of the Senate vote, well above the 67% necessary. The Alaska Purchase had bipartisan support during one of the most politically divided periods in American history.
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