Okay, so it's kinda funny that a British Minister (as in cabinet secretary, not religious post) got detained by the Department of Homeland Security on his way back from a meeting on addressing terrorism. Apparently it wasn't the first time, but I'm sure that, if it helps Britain, Mr. Malik never refuses American hospitality.
The real question: we don't detain Senators, do we? I mean, it's granted that there's a no-fly list where you're guaranteed to get harassed, but is there a white list too? A list of people that it would be politically disadvantageous to mess with? Presumably, a pissed off Senator or even Congressperson might be able to ask some uncomfortable questions about DHS's romp through the search-and-seizure provisions of our Constitution.
Even if we assume that Congress is too impotent to warrant exemption, certainly there's a system in place to ensure that high-ranking DHS personnel themselves aren't exposed to the entirety of their creation, no? Or do they just take the train?
 Yeah, "homeland" sounds funny, but "fatherland" and "motherland" were already taken by the Germans and the Russians, respectively.
 apologies to Gandhi...