Who is in charge? You might think the answer should be obvious.

“This government should be walking on water, there should be nothing it can’t do,” a Whitehall insider suggests, given the rows and rows and rows – and yes, rows – of Labour MPs who line up behind the prime minister every Wednesday.

But, by booting out a small band of backbenchers this week, Sir Keir Starmer’s put the question of his authority back on the table.

Answering the question of who is in charge isn’t so simple after all.

This government has a “backbench they – and we – are surprised to discover they can’t control,” says one senior official.

The financial markets are breathing down its neck, with the country’s debts sky high, and for good measure, what a No 10 source describes as a “deep current of instability” around the world.

Sir Keir’s next one-to-one meeting with President Donald Trump is a case in point – who knows what he will or won’t say alongside the prime minister on Scottish soil next week?

No-one in government can be sure how that is going to shake down, although I was very definitively told we will not be seeing Sir Keir swinging a club with his transatlantic pal.

It is, of course, impossible for any administration to be the master of all it surveys. But convincingly displaying authority, inhabiting its power, is a different task.

And neither all of Sir Keir’s MPs, nor all of the people inside the government are sure it’s being met.

Let’s start with the prime minister kicking out four MPs this week after they had objected to various Labour plans and proposals.

But if Sir Keir really felt in control of his party, why did he need to bother about a group of MPs that wouldn’t even fill a family saloon? And why did he do it, just days before accepting some of the logic of one of those he kicked out, Chris Hinchcliff, over tweaks to proposed planning laws?

Bemused? You wouldn’t be the only one.

Sir Keir’s allies say he always believed there would have to be repercussions for MPs who plot against the government repeatedly, in part because others are asked to defend decisions that might be unpopular or difficult.

So after the welfare fiasco, the whips were asked to make a list of those who had been actively trying to organise resistance to government plans, rather than just expressing objections.

After gathering evidence about MPs’ behaviour, those four were then shown the door, at least for now, to exert discipline over the backbenches.

A senior government figure said: “You can have as big a majority as you want, but if you have no discipline whatsoever it can get chaotic. You can’t get chaotic at a time when the country desperately needs its government to get on with things.”

It was a separate decision to suspend Diane Abbott – again, a choice made by Labour HQ who felt it had no choice but to act, interpreting her comments as repeating a claim that Jewish people don’t experience racism in the same way as black people.

So, “behave – or else”, is the message to the rest of the backbenches, just when they are about to leave Westminster.

But have the moves this week made a difference? One senior MP said: “A lot of people keep wondering, ‘Is Keir beholden to his back benches?’ I don’t think people are like, ‘Oh we’re going to rebel if we’re unhappy all the time’. But there has to be more respect for MPs who are actually out talking to their constituents.”

Another senior Labour figure told me, “No 10 was completely spooked by what happened over welfare – I don’t think backbenchers are running it, but they do have a taste for power.”

Who then, is really in charge, I ask a member of the government. They laugh, and say, “I don’t have an answer”.

The same question posed to another Whitehall figure: “There is no way of knowing,” they respond, suggesting sometimes government, even 12 months in, feels chaotic, with contradictory instructions to officials being given, even on the same day.

It’s no secret, and it’s not surprising, that working out how to run a country when you haven’t done it before is hard.

There are plenty of ministers and staffers who will of course say loyally that No 10 is now firmly in control after understandable teething troubles, who are also somewhat fed up with the noises off.

As one government source reckons, “a bit of loyalty wouldn’t go amiss”. Another insider believes Whitehall is working much better than before. “In the first six months they were disappointed in us, and we were disappointed with them”.

The Spending Review process occupied huge amounts of time and effort across government. Now that is over, it’s not just the government’s purse strings that have been set, but the political priorities alongside. In theory, as that source suggests, “they are now starting to get on with the doing”.

But that optimism is not springing from every source.

One experienced senior official told me: “A government is in charge if it has a plan, but if it doesn’t, it cedes that. They still don’t really have a governing plan, so it feels like the PM is in charge, but it is hard for his writ to be made to work.”

In other words, it’s clearer now, particularly after the big review of spending, what the government wants to do, but not how they plan to do it.

Another senior figure said: “They’re busy and exhausted going to meetings with each other, and producing documents that no-one ever reads, and conversations that don’t lead to anything and telling each other how difficult it is – they don’t inhabit their power.”

And there’s obvious frustration among the government’s own members too, one warning of a passive attitude among some colleagues, who could get to the next election and think only, “Well, I enjoyed driving around in my ministerial car and having my red box”. There is a feeling, like, “Oh, we are here just to manage, not to lead and drive, and that’s not good enough”.

Not surprisingly, one cabinet minister defended the operation, “It’s only been a year, people focus on the problems, if you look at it in the round we have been very, very effective,” they told me.

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Governments are, of course, never short on helpful advice. As well as No 10’s own learning on the job, and plans to improve its operations, like a review of communications across government that is under way, there will be other more formal suggestions in the coming months.

Later in the summer a set of proposals will be published by a think-tank with close links to No 10 and Labour, the Future Governance Forum, that’s chaired by the former senior civil servant, Helen MacNamara.

The review will recommend a new government department, called “Downing Street”, to give this and future prime ministers a more powerful centre of government so that No 10 can make decisions more quickly, and execute its plans more effectively.

Government insiders may not have appetite for any big bang changes, although they have pledged themselves on many occasions to “rewire” the government.

The respected Institute for Government already warned this week that big changes were needed if “ministers were serious” about their promise to rewire the state, concluding in its own research that Sir Keir’s notion of “mission driven government” looks “shaky”, and that government departments had reverted to old habits.

Moving desks and chairs around Whitehall, whether creating new departments or axing the old, wouldn’t exactly make the pulse of the public quicken, but perhaps it ought to be on the agenda for a government that has struggled sometimes to exert its will.

If ministers’ grip isn’t as tight as it might be, and backbenchers aren’t calling the shots, there is no doubt there’s another huge controlling factor.

A senior Labour source tells me, “People like to boil this down to palace politics,” the jockeying for power between politicians, or the competing beliefs inside the party.

Surely not, Westminster enjoying a soap opera about the battle for the party’s soul?

But instead they argue, “The markets are fundamentally a really major part of it – the government isn’t making challenging decisions because it enjoys annoying people, or making life hard”.

It’s true the fights inside and outside the government are so often driven by cash sloshing around or falling down the back of the sofa.

Spoiler, overall spending is enormous but Rachel Reeves keeps a very tight grip on her wallet.

By instinct, Labour politicians normally want public spending to be generous.

Since returning to power they have hiked taxes in order to increase the amount of money going into the NHS particularly a lot.

But the country’s debts are historically massive, and keeping up with the interest payments alone costs more than a hundred billion every year, around double what the UK spends on defence.

The government needs the financial markets to have faith in the UK so that businesses see the UK as a good place to spend cash, but crucially so they don’t increase the costs of borrowing even more.

“The market is the biggest influence on them,” a senior Labour figure tells me. “It is uncomfortable for a Labour government, but none of them want to end up in the Truss situation,” where the City freaked out after promises of huge tax cuts without a plan to pay for them, borrowing costs went through the roof, and she had to say goodbye to her job in less than two months.

At the top of the Labour Party it’s common to find frustration that the rank and file don’t all appreciate what they see as the cold facts.

A senior government source summed up: “The markets are more in charge the more we borrow, so people who want more parliamentary sovereignty shouldn’t be advocating for things that require more borrowing – markets aren’t in charge, but people who lend you money expect it to be paid back.”

No government, at any time, has been able to do exactly what it pleases.

For as long as governments borrow, the entities that lend to them will retain influence.

But having to be careful with cash to keep the markets on side is an acute pressure for Sir Keir Starmer and Rachel Reeves.

As one senior official says “it is the binding constraint”.

And unless and until the economy improves convincingly, or indeed the chancellor or the prime minister have a personality transplant, the markets will exert a mighty force over what they do.

With the markets, ministers and MPs, all jostling, who then really is in charge?

A senior government figure has the ultimate answer – “the voters of course”.

It was the public’s response to the winter fuel allowance decision that led No 10 in the end to drop it.

And when opposition parties zone in on public attitudes to some issues they can in turn force ministers to act.

The public’s current interest in Reform UK occupies and terrifies Labour as well as the Conservatives.

Opposition politicians might not have the power to make decisions, but the issues they campaign on along with their fellow travellers and supporters can shape what happens at the top.

As this political season draws to a close, Nigel Farage will join us live in the studio tomorrow.

But in the end, of course, it is always you that has the say, you who can determine whether Labour prospers, whether in a few years time you give them another chance.

But to persuade you of that, the government will want to look more convincingly in control than in its first twelve months.

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