Imagine being in an extraordinarily high stacks situation with billions of dollars and tens of thousands of lives on the line. Your ability to think logically and critically is vital to the success of your enterprise. You have perhaps a couple of hours to make a fully interrogated strategy with multiple levels of complexity and contingency.
And just as you begin this seemingly herculean assignment... you develop a hard-on. Blood evacuating your brain to power your penis. In a matter of moments, the male brain has been starved of a fundamental ingredient for high end mental processing.
This is why nations fail.