I would argue that all five of the above points are significant, but the most important reason to study history is because it is the only field that does not have a technical language and unlike other fields that specialize and are narrow, history is about everything, thus it affords the student a world-view perspective, although one that may serve to broaden the mind or one that can 'narrow' or reduce the mind toward greater dogmatism.
If we lived in Victorian England, we would not be exposed to the same interpretation of social classes' role in society during the Tudor dynasty, nor would we have the same attitude toward the role of the church in society, given the inevitable social discontinuity and secularization between King Henry VII and Queen Victoria. The same holds true if we compare how history was taught in the southern US states in the 19th century versus today after the Civil rights movement and an African-American sitting in the White House. All of this suggests the subjectivity of an otherwise empirical field of study.
But how different was the goal of learning history in Victorian England than in the US before the Civil War, during the Cold War, or today in the 'war on terrorism' epoch? Is this empirical field of study ultimately dominated and guided by societal mega trends and thus subjective if not dogmatic at some level? Curriculum is always revised to reflect societal political and ideological trends and prevailing social values. The current trend in American historiography is that there are "many Americas" reflecting the country's heterogeneous cultural composition and evolving values.
However, the are always 'national enemies' demonized in subtle or direct ways in the field of history. When I was in elementary school in Greece and high school in the US, there was never any talk about the role of gays and lesbians in history, or of the contributions made to Western civilization by the Arabs and Chinese, to mention two of many examples. The new Cold War against Islamic 'terrorism' (unconventional warfare) has replaced the old demon Communism. Therefore, there is thematic continuity of enemies against the state, against American democracy, a process that afford identity through the concept of 'separateness' (American Exceptionalism) has to do less with learning and a great deal with indoctrination.
Historical interpretations are a reflection of changing times, thus history, the analysis of past empirical events, people and institutions is subordinated to an ideology that is invariably nationalist. One hundred years from now, historians will not view the Cold War in the same manner as secretary of State Dean Acheson and Russian foreign minister Andrei Gromyko did fighting the early Cold War amid the nascent nuclear arms race and seeing each other's country as 'the enemy'.
Besides ideological influences that shape historical interpretation, something that is nearly unavoidable, there is the added problem in contemporary culture of presenting history from a superficial and entertaining manner that reflects the age of mass media/entertainment. As a historian in the U.S., I found it disturbing that increasingly the focus on substance was preempted by style, superficialities, appearances and above all the cult of personality and 'entertaining' material rather than the painful one that forced students to think. In short, history as a TV show about the rich and famous, history as a theatrical play about heroes and villains, history appealing to emotion. As the mass media has gone this route, it has also influenced the course of education and this method makes indoctrination much easier thus serving a political goal.
T.S. Elliot's "Hollow Men" is just as appropriate today as when he wrote it, even in the field of higher education. But 'hollowness' may actually serve a number of goals and that is why it persists, and not necessarily because people choose to be hollow. Besides history that has been used as indoctrination, not just in the US but in all countries, the field of Education that train people to become teachers also contributes to the problem. With apologies to many excellent education professors for generalizing, the "hollow trend" is a reflection of college courses in Education Departments that focus so much on methods, rather than content, which ought to be empirical and historical. Even when content is the focus, historical figures are rarely given a multi-dimensional character that best represents them.
The late Professor Ronald Hilton (Stanford University) was right that Stalin has been stereo-typed, as have Napoleon, Caeser Augustus, Mao, Kennedy, De Gaulle, and countless others. One reason is because political leaders are easy to stereotype, and teachers have an easier time stereotyping than going through lengthy and complex explanations. Superficial analysis is the easy, painless, and popular way of explaining complex multi-dimensional personalities, institutions and event. Moreover, contemporary culture rooted in the atomistic value system focuses far more on stereotyped personalities rather than complex structures, and it is easier to stereotype structures than to unravel their complexities.
In a conversation I participated among university professors before Gorbachev, one of my colleagues asked the other who was a Russian specialist if there was anything at all that was positive about Soviet society, any redeeming quality to a system that was on its way to collapsing in the 1980s. The Russian professor's reply was that absolutely nothing about Russia was good, because the ideology of Communism on which Russian society was built was evil in contrast to the US that serves as model of democratic society in the world. This view reflected dichotomous Cold War thinking that pervaded from the State Department to universities, leaving the student of history with nothing more than an impressionistic and partial view of Russian history and society.
Was Nicolo Machiavelli incorrect to argue in THE PRINCE that people judge by appearances whether in politics or every day life? And is it not easier and simpler for the mind to be immersed in indoctrination than to figure out a universe of complexities like an astrophysicist? Perhaps the existentialists are correct to argue that there may be an innate proclivity in human nature to reduce people, events, policies, etc. to simple terms that best reflects one's world-view of objectifying the other, and of making sense of the outside world in simple terms".
Regrettably, complex institutions, policies, and events are explained in the same manner by many educators, journalists, and politicians, thus education can be, but certainly not always, more about indoctrination than it is about having the benefit of multiple perspectives and encouraged to enjoy the freedom to think for oneself and to gain greater appreciation of the other and the broader world. Not that the trendy political correctness of multiculturalism carried to extremes does not pose a different set of problems, raising questions about the theoretical and practical difficulties in trying to teach history as a vehicle of enlightening students rather than indoctrinating them.