Is there a comprehensive system for identifying course objectives?
Perhaps the closest thing to a system would be the objectives that were developed for the full curriculum?

An example from my area. In biology, a recent call encourages universities to be less focused on subdisciplines and more on core concepts and competencies. After many meetings, biologists settled on these:

Core concepts: evolution, structure and function, information flow, energy pathways, systems.

Competencies: application of the scientific method, quantitative reasoning, modeling and simulation, interdisciplinary connections, effective communication.

If I were writing out my learning objectives for the lecture on photosynthesis, I might list that photosynthesis fits into structure/function and energy pathways core concepts, and I would be motivated to include a discussion of a classic experiment so students can practice the scientific method and some calculations for students to apply quantitative reasoning.

I would imagine that history (or any other discipline) likely has a similar  list of important concepts plus important skills they want their students to have.