If one referendum is ‘democratic’, why should a second one be ‘undemocratic’? That’s what the Brexiteers are arguing; most recently the awful Iain Duncan Smith in response to Tony Blair’s call for a rethink of last year’s EU vote: http://www.bbc.com/news/uk-politics-38996179.
I can see the practical objections to repeating referenda over and over again until you get the ‘right’ result; but not any reasons of democratic principle. In this case I’d have thought the argument for trying to elicit a considered verdict on the question from the British people, freed from the extraneous considerations that marred the first vote (see https://bernardjporter.com/2016/06/16/is-it-really-about-the-eu/), and in the light of the knowledge that’s now beginning to accumulate of the probable problems and disadvantages of Brexit, was pretty unanswerable. Otherwise we’re staking our whole national future, not on what the people necessarily want today, but on what they thought they wanted at one brief and fevered moment of time in the past.
Again: what is particularly democratic about this?