George Eaton is political editor of the New Statesman.
The leader's decision to fight the rebels sets the stage for a new leadership contest or a protracted legal battle.
Margaret Hodge and Ann Coffey have submitted a motion ahead of Monday's PLP meeting.
Remain believed that economic risk would deliver victory. But the Brexiters had a more potent weapon: immigration.
Remain refused to speak of the benefits of increasing immigration. Leave refused to speak of the costs of reducing it.
It is the EU of tomorrow, not today, that the Labour leader truly supports.
A narrow Remain victory will likely result in a second vote under a future Conservative government.
The battle-hardened London mayor and Scottish Tory leader relentlessly exposed Leave's mendacity.
Labour leader says he won't be responsible for "people's decision" and that "there may well be a Leave vote".
The PM came out fighting after being derided as a "21st-century Neville Chamberlain".
That these institutions attracted someone of Cox's calibre suggests they are in better health than many suggest.
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