During the last Parliament, George Osborne’s tussles with spending ministers were eased, first, by a shared determination by both Coalition partners to tackle a deficit that, in 2010, was the highest since the Second World War (and threatening to become the worst in the EU); second, by having Labour’s inheritance to squeeze and, third, by the commitment of David Cameron, the Chancellor’s closest political colleague, to serve as Prime Minister for the whole Parliament.

None of those conditions now apply.

The deficit has halved as a proportion of GDP, the Government has a formal majority of only 12 (under the Coalition, it had one of over 70) and, as Osborne’s tax credit rebuff has shown, the combination of dissent in the Commons and defeat in the Lords can bring down plans to reduce that deficit further.

Labour’s 13 year term is now five years old rather than few months distant.  Public satisfaction rates with the public services confirm that there was a lot of fat in the system for the Chancellor to slice off in 2010.  There doubtless still is.  But as each year passes, less of Labour’s settlement remains.  And now that the economy is growing again, the sense of urgency that accompanied deficit reduction five years ago is absent.  In any event, the Government has reduced its options by its pledges to protect the health, defence and aid budgets – and, more broadly, by its promises to shelter richer, older and retired voters from the continuing public spending scaleback.

Finally, Cameron has promised not to contest the next General Election as Party leader, and the Chancellor wants to succeed him.  This context gives the latter’s rivals a new incentive to frustrate him, as Boris Johnson has artfully striven to do during the tax credits imbroglio.

For these reasons, the run-up to the Autumn Statement, and its aftermath, is likely to be turbulent.

Less than a month ago, Osborne was hailed at the Conservative Conference as a master strategist on course to be the next Prime Minister.  In the wake of this week’s Lords’ vote, he is being reviled, in some quarters, as a cocky bungler whose leadership prospects are now toast.  Both views cast light on nothing (other than the fickleness of the Westminster Village).  The truth lies elsewhere.  Like Russia in the apocryphal saying, the Chancellor is never as strong as he looks, never as weak as he looks.

If Britain votes to stay in the EU by a convincing margin, Osborne will be in a good position to succeed his friend.  If it doesn’t, both will go down together.  The danger for him in meantime lies less in backbench MPs permanently holding the tax credit retreat, or the Omnishambles Budget of 2012, or anything else against him than in the interplay between his plans for the public finances, his leadership ambitions, the EU renegotiation – and opposition by some of his Ministerial colleagues to at least two of those three.