Ilya says yes (based on what I think is an originalist or textualist interpretation of the Constitution), I say no. A few further comments/questions.
1. Assuming both presidents violated the Constitution, Ilya believes that Obama’s constitutional violations (Bergdahl, Libya) are more serious than Bush’s were (torture, surveillance). Although I said the opposite, I’m not sure. How does one measure the seriousness of a constitutional violation (as opposed to the unwisdom of the underlying action)? Bracketing the harm done by these actions, it seems to me that Bush’s would be harder to defend based on conventional legal reasoning (again, if you assume that the president has no authority to defy Congress), but I’m not sure why. Ilya also thinks Obama’s actions caused more harm to the nation than Bush’s did. I don’t know.
2. Ilya tells a story in which we learn over history that certain policies (torture, surveillance, prisoner exchanges, military interventions) are unwise or presumptively unwise. Congress incorporates this understanding into law. The president, because he is motivated by short-term political considerations, violates the law. This is why Congress should be given the power to control executive action. My view is nearly the opposite. To take one of many examples, I believe that Congress’ policy toward Guantanamo Bay reflects short-term political considerations. Or consider the debt limit conflict.
3. Ilya seems quite certain that the prisoner exchange was unwise as a matter of policy. Based on what? Prisoner exchanges (including exchanges with “terrorists”) have been routine throughout history. I believe that abandoning Bergdahl to his fate with the Taliban would have been a blow to national prestige and, I suspect, morale in the military. What would have been the political reaction if the Taliban had executed Bergdahl and then it leaked out that Obama had turned down an offer to make an exchange?