If it all goes pear-shaped for Hillary, who will the Democrats field?

The email controversy may unseat Hillary Clinton. That’s the sum and substance of all the froth about the fact that she was heedless enough (it has to be said) to use a private email address during her time as secretary of state.

The controversy reminds people what they don’t like about Hillary. As a Clinton, she seems to work to the principle that she is, somehow special. Above the law. Other Americans have to comply by government rules. But not Mrs Clinton. Why not? What gives her the right to do as she pleases? That’s the question that many ordinary Americans will ask – and they would be right to do so.

With her candidacy for Democratic nominee president not yet announced, but widely assumed, it is possible that the controversy will simply fade away with time. But I rather doubt that. This is red meat – not just to the Republicans, who can endlessly allege stuff about Benghazi in deleted emails from Mrs Clinton’s personal email address – but to anyone who wonders why the US works. Because the rule of law is the rule.

If anyone, Hillary Clinton or J Smuck, flouts it, the consequences should be the same.

So what happens if Mrs Clinton’s so-far non-existent campaign implodes? There seem to be four potential Democrat candidates right now – Vice President Joe Biden, former Maryland Governor Martin O’Malley, Vermont Senator Bernie Sanders and former Virginia Senator Jim Webb.

Then there’s Elizabeth Warren.

I’d plump for her. Or Sanders.

If only.