It has often been claimed by people all around the world (Americans included) and of all political stripes that Americans are hopelessly ignorant and naive about the world and world history. I have to agree, Americans are far less aware of the world and more unaware of world history than even the people who most resemble them culturally; Canadians.
Now, there are a lot of explanations that have been thrown around: Americans are too in love with themselves to care about the outside world or
American culture is much more anti-intellectual than European cultures or the American education system is lousy.
Some of these might be true to some extent, but there are two reasons why Americans are ignorant of the outside world. Simply because America is much more peaceful than people give it credit for and America isn't as effected by most nations as they are effected by America.
Take a look at European history, what has been the one constant in European history up until 1945? War. It seems that every European nation has gone to war with ever other European nation in its history. This has even lead to some oddball wars, such as Danes versus the Irish and Norwegians against the Scots. Europeans have a very good reason to pay attention to their neighbors and even when they do not pay attention to their neighbors, their neighboring nations histories and their own often overlap. How could a Pole be knowledgeable about their own history without picking up a decent amount of German, Lithuanian, and Russian history? How could the French be knowledgeable about their own history without learning some English, German, Belgian, and Spanish history?
And it is not just confined to Europe, it also extends to Latin America as well. Latin American countries in the 19th to mid 20th century have waged bloody wars against each other that pale in comparison to American interventions in the region. Paraguay fought a bloody six year war (1864-1870) against Uruguay, Argentina, and Brazil, estimates range that between 35-60% of the population of Paraguay was killed (making Paraguay the nation that has suffered the most in a war percentage wise). Do you think Paraguayans aren't familiar with this time in their history and who was responsible for it? Also, the current borders of Latin American nations are very different than the original borders. For example, Bolivia used to have coastline at one point.
Now, how many incidents like that have happened to the United States? Sure, Canada (which was a British colony at the time) and the United States went to war in 1812, but that war was a stalemate and happened a long time ago by American standards. Also, since Canada was a British colony at the time, Canada is not often viewed a belligerent in that conflict. There was also the Mexican-American War (which the Mexicans are certainly well aware of), but it was a relatively easy war and it caused the US to gain huge amounts of territory that was mostly unpopulated (not counting Native Americans) or populated by American settlers already.
Now, only two nations have land borders with the US. One wasn't an independent country when the US went to war with it and the other conflict was mostly overshadowed by the Civil War which occurred less than twenty years later.
By world standards, that really isn't all that bad. Compare to the amount of border clashes, invasions, and wars other nations have gone through with their neighbors. Even when you include the dozens of interventions in Latin America, they were mostly small scale troop deployments aimed at protecting American investments in the country during a time of conflict or evacuating American citizens. Many of them are hardly worth a mention in the grand scheme of things.
So while Americans shouldn't be proud of their ignorance, Americans should be proud in the root of their ignorance. Sometimes not having to learn another's history isn't such a bad thing.