Tensions between the Coalition partners have been vivid and intense for some time. But what are now becoming increasingly marked are the tensions within the two governing parties. Conservative MPs stir against David Cameron; Boris Johnson is cheered when he speaks and is touted as a more popular leader; former ministers who were victims of the recent reshuffle nurse their wounds and could yet become dangerous enemies.
Meanwhile, a similar sequence is unfolding within the Liberal Democrats. There is persistent speculation that Nick Clegg might not lead the party into the next election; Vince Cable is being wooed by Labour and has been known to be in text contact with Ed Miliband; one or two Liberal Democrats have doubts about the Cabinet reshuffle and wonder privately whether their leader is out of his depth.
Sad to say, all these various manifestations of discontent are starting to drown out policy. Over the past few days, the Business Secretary has unveiled several initiatives aimed at generating economic growth. They have been largely well received across the political spectrum, and deservedly so. Indeed, yesterday's proposed changes to Britain's employment rules were an astute balancing act, making the labour market more flexible, but without the extremes measures advocated by some senior Conservatives.
But the reception to Mr Cable's high-profile initiatives has been too often refracted through the prism of internal Liberal Democrat dynamics. In fact, in recent months the Business Secretary has commanded more attention for his declaration that he no longer rules out standing for the leadership, and even for his vaguely warm relations with the Labour leader.
Similarly, Mr Clegg's policy proposals since the summer break seem aimed as much at strengthening his position within a worried party as at early implementation. Reports that he would be willing to accept further cuts to benefits, if the Conservatives back his proposals for a wealth tax, suggest negotiations are at a very preliminary stage, not least because George Osborne swiftly ruled out a wealth tax when it was first proposed.
But the Prime Minister is showing signs of similar constraint. Much of his Cabinet reshuffle, and a number of his recent declarations, have been shaped by the need to reassure the right wing of his party. In all likelihood, much of the current plotting will lead nowhere. Such is politics. It would be precipitous to predict a coup against Mr Cameron yet. Mr Johnson may perhaps not even be an MP by the time of the next election. And, although ambitious, Mr Cable shows no sign of wanting to remove Mr Clegg and, so far at least, very few voices have called for the Liberal Democrats' leader to stand aside.
Even without a definable climax, however, such rumblings are still significant. They are symptoms of a deep unease as the Coalition's differences over policy are exacerbated by struggles with continuing economic gloom. If Mr Cameron were either strong or popular, there would be no great interest in Mr Johnson. If Mr Clegg had achieved some of his early objectives, Mr Cable's newly discovered ambitions would make few waves.
For both the Prime Minister and his deputy, therefore, the looming party conference season is of considerable importance. Although Mr Johnson and Mr Cable will also have their moments in the sun, conference season is a time when party leaders take centre stage. Both must use them to set out their course more clearly and convincingly. As of now, it is hard to see how the Coalition maintains momentum for another three years. If the verdict remains when the conferences are over, the current febrile mood will become much stormier.