The citizenship part is a red herring. To me the main event is the hypocrisy.
Can you imagine if a reservist had refused deployment orders on the grounds that Bush is AWOL from the TX National Guard? The osik would have been hitting the fan by the ton! Fox news commentators would have been bouncing off the ceiling tiles about “failure to respect the office” and “disobeying a lawful order” and “treason” etc etc. But about this? Crickets….
History is clear that partisans demand unquestioning “respect for the office” of President only when it is their President.