There are many reasons why Jeremy Corbyn remains safe as leader of the Labour party. His continuing popularity among party members and Labour's likely (but not certain) win in the London mayoral election both means he will withstand whatever immediate threat to his position might follow a poor performance in the upcoming local elections.

But the biggest reason he isn't going anywhere is the increasingly baffling and self-destructive behaviour of his internal party opponents.

Over the past week the self-styled Labour 'moderates' have launched a truly bizarre campaign in defence of corporate giant McDonald's. It began at the weekend with a story in the Sun on Sunday revealing that the party's ruling executive had rejected an application by the fast-food chain to pay for a stand at Labour's upcoming party conference.

Upcoming Labour MP Wes Streeting told the paper: "I'm exasperated that we should throw away £30,000 worth of sponsorship like this.

"It smacks of a snobby attitude towards fast-food restaurants and people who work or eat at them."

But does it really? After all, this is not the first time that a company's sponsorship has been rejected by Labour. Three years ago outsourcing company Carillion were rejected due to their treatment of employees and alleged blacklisting of union workers. McDonald's corporate behaviour is clearly not on same level as this, but their routine use of zero-hours contracts, poverty pay levels and, most importantly, their refusal to recognise trade unions, are all legitimate reasons for the party to refuse their money.

Indeed, these are all issues that the Bakers' Union which represents fast food workers, and who recently won a seat on Labour's NEC, are currently campaigning on. You can watch Politics.co.uk interviews with McDonald's workers campaigning on those issues below.

Now, you might think that MPs representing a party which was founded with the central aim of championing workers' rights, would be on the side of such workers. And you certainly wouldn't expect them to be manning the barricades for their bosses. But that is exactly what a number of Corbyn's leading opponents in the party have done this week.

Streeting told the Sun: "McDonald's may not be the trendy falafel bar that some people in politics like to hang out at but it’s enjoyed by families across the country."

Now leaving aside the suggestion that anyone who is a critic of McDonald's employment practices must be a chickpea-chomping, lentil-weaver from Islington, there is something deeply disingenuous about Streeting's comments.

For a start, just because a company's products are popular, does not mean that the company itself is exempt from criticism. Just because you enjoy a Big Mac doesn't mean you have no sympathy with the demands of the people who made it. Similarly, just because Labour's NEC are implicitly criticising that company, does not mean they are criticising the people who buy from them. If you attack the board of McDonald's, it doesn't mean you are attacking the people who queue up with their kids for Happy Meals.

To suggest otherwise is to either completely misunderstand the intent of such campaigns, or to deliberately misrepresent them. The fact that the Bakers' union are campaigning for McDonald's to treat their employees better does not mean that they are campaigning against the continued existence of the fast food chain. In fact it is quite the opposite. They are campaigning for that company to continue to flourish, but to do so in a way which is fair to the people who work for them.

Labour MPs continue to have a difficult relationship with their leader

This is all so obvious as to be barely worth pointing out, yet despite this Corbyn's internal critics are determined to keep making a major issue out of Labour's rejection of McDonald's sponsorship. Earlier this week several leading 'moderate' Labour MPs personally confronted Corbyn about the issue and senior Labour figures told Politics Home that they plan to fight to overturn the ban.

Now far be it from me to offer advice to Labour MPs on how best to get rid of their current leader, but it seems to me that if Corbyn's many critics in the party have any hope of dislodging him, they need to choose their battles much more wisely than they currently are.

Jeremy Corbyn became party leader partly on the back of a grassroots movement which believed their party had drifted too far towards corporate interests. It was this belief, that the party of the Labour movement no longer represented ordinary working people, which led to Corbyn's crushing victory. The biggest turning point in last years' leadership election came when the party, then led by interim leader Harriet Harman, opted to back the government welfare squeeze. Andy Burnham's decision to acquiesce with that decision killed off any hopes he had of winning the contest. From that moment onwards, Corbyn was able to pose as the sole champion of the new Labour left against a party establishment which looked increasingly out of touch with its own members.

Fast forward a year and Corbyn's opponents seem to have learnt almost no lessons from that campaign. Not only have they not even begun to consider how best to win over the party's overwhelmingly left-leaning membership, but they seem determined to reinforce all of the members' existing perceptions about the priorities of the Labour right.

To paraphrase the New Statesman's Stephen Bush, Labour members now know three things about Corbynsceptic MPs: They like nuclear bombs, bombing Syria, and Big Macs. As long as that perception persists, and as long as the Labour right continue to choose such utterly self-defeating issues to fight over, then Jeremy Corbyn will continue to look untouchable.