DM says that DC asked for safeguards against “phantom threats.”
If the safeguards weren’t needed then there would have been no harm in the 26 giving them.
The fact that the safeguards are needed is obvious from the fact that the 26 could not to give them.
(If you ask someone to promise not to do something and they refuse to promise, you can be certain they will do what you don’t want.)
By asking, DC revealed the truth of the situation. By refusing, Sarkozy confirmed it. After that the veto was inevitable.
Those who say DC should not have asked, implicitly accept the financial consequences of such inaction – and need to explain how they would deal with the subsequent loss of tax revenues from a shrinking City.
(Note the FTT – which is a tax on pension funds and other investors, not bankers – would not raise money to be spent in Britain – the money would go to the EU to use for projects in far flung places.)