History can be very important, not only from understanding what happened but from having a thorough understanding of why it happened. A classic example would be a case where someone states that WWI started due to the assassination of an archduke without understanding the geopolitical context. It's important if you ever find yourself in a situation where you need to make decisions that impact the future.
Does it really matter what the political context was? If president Obama was assassinated by someone in Iran, you know the shit would hit the fan. President Obama assassinated in any foreign country would start a huge international conflict and potentially start a war.
edit: 9/11 is another example of terrorism starting a war
The real lesson to learn: destroy
all terrorist groups in your own country. Even the ones you agree with on a philosophical level. If they do something crazy like assassinate the leader of another country, even if it's a leader you think is a douche, it could cause a war. Then again that's basic common sense. Killing important people causes problems? No shit.
When I went back to college in 1999, there were certain professors know to give you at least a B if you bitched / confronted them. Piss poor teaching.
And now we know how alkemyst passed his classes. Mystery solved.