There are lots of ways to answer this and one of them is that studying history makes you a better citizen and our public universities have an obligation to produce good citizens. History education is essential to a republican model of government. Engineering is not.
Am I missing something here? In what universe would an engineering student ever study history?! Do many history students study engineering?! I *enjoyed* history at school, and I was *good* at it. But no way would I ever have studied it at university.