We'll know the White House is in full code red mode if President Trump fires Sessions and replaces him with Giuliani, who matches the president's pugnacious personality and built a career as an ambitious prosecutor before turning to elected office. Unlike Cruz, Giuliani holds no elected office now and hasn't even been a candidate in nine years. He has less to lose and could more likely bend to the president's day-to-day whims. And if one of those whims is to fire special counsel Robert Mueller who's leading the Russia probe, all political hell will break loose.
It's not that Giuliani doesn't have the capacity to be as independent as Cruz, it just seems a lot less likely at this stage in his career and his lack of a national base to consider. Cruz probably still wants to run for president again someday — that doesn't seem to be the case with Giuliani.
Here's the bottom line: If the Trump administration wants to hold on to any credibility at all, the president needs to back off of Sessions and find another way to lash out at everyone's Russia-based obsessions.
It's not that Sessions doesn't have real political flaws. Most troubling are his positions on turning back the clock on legal marijuana laws and allowing the government to seize more private property in criminal cases. And it's also not that the constant Russia focus hasn't also damaged the Democrats' brand. But none of the negatives about Sessions are greater than the damage President Trump would do to himself and his entire political agenda if he lets him go.
It may seem like the White House has other options besides keeping Sessions on board, but it really doesn't. The only question is whether President Trump will see that before it's too late.
Commentary by Jake Novak, CNBC.com senior columnist. Follow him on Twitter @jakejakeny.
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