1. U.S. unipolarity
2. Rules trump everything else
3. All peoples and societies yearn for democracy
All of those assumptions have created a degree of blindness. The first breeds complacency and a lack of perceived need to understand other countries' interests or consider the overall balance of power. The second ignores geopolitical considerations e.g., the notion that geopolitics can bring opportunities and challenges/advantages and disadvantages. The third oversimplifies the causes of internal unrest.
As a result, activities by the Russia and China, among other nations, aimed at furthering their critical interests and long-term ambitions, the impact of such policies on the the regional and global balance of power, and how such states have leveraged what they perceive to be an advantageous balance of power (e.g., Russia's rapid exploitation of Ukraine's political unrest to gain control of Crimea and annex it) have allowed them to fly under the proverbial U.S. policy radar. That the decline in central authority in parts of the Mideast have witnessed a reanimation of bitter sectarian rivalries that the U.S. mistakenly interpreted as democratic uprisings (hence the misplaced term "Arab Spring") have led to surprise and disappointment as democratic gains failed to materialize and terrorist groups e.g.., ISIS, exploited evolving power vacuums.