There are principled and pragmatic reasons for the Chancellor to act in his first Budget of the new parliament.
The Chancellor misjudged the mood by joking about "Bennites" in response to a question on suicide bombing.
The party must be more nimble and shrewd in its economic positioning than in the last five years.
The party will need to decide whether to make the case for investment or to embrace fiscal conservatism.
Ed Balls's less stringent plans mean a dramatic gap with the Tories.
The Chancellor has vowed to cut £12bn from welfare - but he's announced just £3bn of savings.
The Chancellor has made a virtue of coalition government and of missing his deficit targets.
The Chancellor neutralised some of Labour's strongest attack lines - but there was no knock-out blow.
The Chancellor later tried to wriggle out of a one-to-one debate, saying that Danny Alexander should also be invited.
Osborne has at least one big card left to play - but it might help the Conservatives less than they hope.