It is a beautifully sunny morning in Brighton, and many Labour members here have a spring in their step. I think only now is the reality sinking in. The man more than half of them voted for really is their party leader.
Somehow party conference makes it real. There are the ritual photo-opportunities - the arrival at the hotel, the tour of a local business, the appearance at regional receptions, the Andrew Marr interview. Suddenly it isn't Kinnock or Smith or Blair or Brown doing these things - it really is Jeremy Corbyn.
Labour's most unlikely leader. The 200-1 shot only a few months ago. And the man most Labour MPs definitely didn't want.
The pressure now is on them not to cause trouble here. In public they are saying - let's give him a chance, let's see how he does. They fear they wouldn't be forgiven if they started making trouble so soon.
They have no choice of course. The size of Mr Corbyn's mandate makes him unassailable (as Mrs Thatcher once said) - for the time being.
But privately many feel he is simply unelectable. And even if he manages to win back some Old Labour voters, they fear he won't reach out to Middle England - and those voters in the south Labour desperately needs.
The conference centre is just across the road from where they filmed "Oh What a Lovely War" - a movie which Jeremy Corbyn probably enjoyed. One of its songs is "There's a long long trail a-winding". That's what Labour faces.
There is an uneasy truce here in Brighton for now. But there could be some fierce battles ahead.