There are obvious issues with positioning yourself as a change candidate in a White House race while serving as the US vice-president.

For one, it requires considerable political dexterity to simultaneously claim credit for the things that have gone well in your administration and distance yourself from the parts that have gone disastrously wrong.  

For another, it is hard to explain why you have not already done any of the things you are now proposing.

There’s also the inescapable fact that anything you do say to distance yourself from the administration you serve may upset your boss, not to mention making you look disloyal.

Kamala Harris has been grappling with that dilemma since she replaced Joe Biden as the Democrats’ 2024 presidential candidate in July.