A hard to understand paragraph [closed]

How can the bolded part of the following text be expressed in the simple language?

While the principals are a cut above this level of qualification the incompetence of the American government to do business requires a rethinking on our part of why there have been so many frustrating failures to deliver on their part.

Here's a critique rather than a solution

1. There are too many (potential) clauses in the sentence. Target each sentence to make one point, and one point only.
2. The "rethinking on our part" is vague. What rethinking is required? Or alternatively, what was the thinking or expectation going in, and what should have been the thinking/expectation in hindsight?
3. "On their part" should not be required once you are clear on 2.

Hope that helps!