The military operation in California illustrated many tenets of US doctrine. Additionally, the campaign demonstrates the utility of several theorists, both military and otherwise, for examining combat operations. Most of all, this campaign demonstrates the tension found in some key doctrinal concepts. These include risks and benefits of Mission Command, the challenges of developing shared understanding, and the importance of understanding the environment, especially the tendencies of a military theater. Tension also resides between the phases of major combat and the stability operations that follow. The operation in California demonstrated that the transition from combat to stability is not a one-way street. Commanders found themselves moving between the two types of operations. In California, commanders found that they were properly resourced to conduct initial combat operations but ill-resourced for stability operations. This caused the operation to slide back into conventional combat and created a situation where the force, after succeeding in major combat operations at the outset, struggled to defeat the enemy a second time. In fact, US forces were defeated in several conventional engagements before adapting to the situation and eventually prevailing. The operation also demonstrated that in many cases the combination of uncertainty, chance, friction, and the natural environment can combine to challenge, if not defeat, a military force. Sometimes the enemy, while interesting, is not the problem. The US military forces in California encountered this confluence of factors several times. At San Pasqual, it nearly resulted in the complete loss of the Army of the West. At the very least, these variables created conditions that led to operational setbacks for US forces and threatened the strategic success of the entire campaign.

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