Mr. Sessions, Your 'Extraordinary Circumstances' Are Here
In March, Attorney General Sessions wrote to three Republican congressman, declining to appoint a special counsel in the matter of the FBI, CIA, Obama administration and... and... frankly, I don't know what to call it, since there is so much from the Clinton Foundation to the emails to the FISA court to who knows what.... because, the AG said, a special counsel necessitated "extraordinary circumstances."
I sympathized somewhat with Sessions at the time. Special counsels do not have the best track records. Often they are appointed for dubious politicized reasons. In the Valerie Plame case, a special counsel put Scooter Libby in jail for outing the insignificant Plame as a CIA agent when she was already easily identified in Who's Who (not to mention that the never-indicted Richard Armitage, not Libby, did the initial public outing anyway).
[UPDATE: As several commenters have correctly noted, Libby was indicted for the ever-popular "lying to the FBI," not for outing Plame. I knew this and apologize for being so sloppy. But it's worth noting that is even worse, virtually, as someone said, a "set up."]
Now we have the interminable Mueller "Russia Probe," so named because it was supposed to be looking into Russian involvement in the 2016 election but seems to be investigating everything but. Democrat pollster Mark Penn isn't the only one of his party to realize this has been one elongated farce and actually damaging to the Dems with FBI officials dropping like flies either through quasi-firings or potential indictment. The public is somewhere between bored and nauseated. That Republicans are suddenly leading in the generic polls is almost certainly related.
Now we have a situation that qualifies as an "extraordinary circumstance" if anything does. It is becoming increasingly clear that there was and is a plot at the highest levels of our government involving the FBI, the intelligence agencies, and the Obama administration to block and then undermine the administration of Donald Trump.