It used to be said that loyalty and unity were the secret weapons of the Conservative Party. The weapons have gone missing. They were cast aside when the party committed regicide on Margaret Thatcher in 1990. Unsurprisingly, the party did not claim them back in the early years of Opposition, when election defeat demands internal debate. But what is much more surprising is that these traditional Tory strengths are still not visible now they are back in power.

The reverse applies to Labour. As an innocent student journalist in the 1980s, I asked the equally innocent MP, Michael Meacher, to describe the mood in the Parliamentary Labour Party. He replied in a matter of fact manner that it was a "cauldron of hate". If political journalists wanted to write about splits, division and sheer hatred, they turned to Labour. Unity finally broke out only after four election defeats. If it hadn't after such a series of electoral losses, it was never going to do so.

By 1997, Labour's humbled activists and slightly less-hateful MPs would have rallied around a programme calling for a 5p top rate of tax and the re-incarceration of Nelson Mandela. The hunger for power was overwhelming. What is surprising is the degree to which the same discipline still applies now after a traumatic election defeat and a weird fraternal leadership contest.

After the election, some commentators predicted civil war, especially if Ed Miliband beat his brother. Far from there being a schism, Labour still maintains an appearance of unity. It may only be a façade, but when it comes to unity, a façade is often the best it can get.

After Tuesday's reshuffle, the shadow Business Secretary, Chuka Umunna, expressed delight at the recruitment of Andrew Adonis as part of his team. Seen as a so-called ultra-Blairite, Adonis was an early target of the Conservative leadership that yearned for a big defection. Instead, Adonis is back on Labour's frontbench in the Lords. Although rising up the ranks partly through the leftish Compass group, Umunna has worked with Adonis informally for several months on industrial policy and also liaises closely with Peter Mandelson, Labour's last Business Secretary.

In a separate counter-intuitive move, Ed Balls and Mandelson wrote a joint article on Europe this week, not a policy area where there was obvious common ground between the duo.

As a third example of many, David Miliband could have seized the weapon marked "loyalty" and thrown it out of his brother's reach. Instead, he has behaved with public sensitivity and restraint in spite of his intense frustration and the unavoidable awkwardness of his situation. So far, he has not provided his party's opponents with a single damning quote against his younger brother, even a coded critique.

In contrast, no code is required when some Conservative MPs reflect on their colleagues. Nadine Dorries has delivered the most troublesome quote of this parliament, condemning Cameron and Osborne as out-of-touch posh boys, an attack as unfair as it has been highly effective. Separately, when I was having a relaxed conversation with a senior Conservative about who might be his next leader, the name of George Osborne inevitably came up. Without hesitation, he replied, "We'll kill him." I am sure he did not mean this in a literal sense, but the metaphor is in regular use. Recently, a Downing Street insider was quoted as wanting Andrew Lansley taken out and shot. A similar raging intensity marked the elections yesterday to the Tories' backbench 1922 Committee, an echo of the Major era when many shots were fired in these internal contests.

Of course, there are important limits to this marked reversal of roles. Labour's unity is fragile. There are genuine ideological differences within Labour over public service reform and, to some extent, over economic policy. There are anonymous figures ready to brief against Ed Miliband and, for different reasons, Ed Balls, if the current rosy political context changes for the worse, which it is bound to do. Only a month ago, there was talk about whether Miliband would lead them into the general election. With the Conservatives, it is sometimes difficult to discern what the internal anger is all about. They are united in their Euroscepticism and the leadership pursues a set of ideological reforms that would make Mrs Thatcher nervy.

Nor is unity always a virtue. Labour's fear of internal debate can be stifling and risks making the party seem managerial and lifeless. The Tories' occasional acts of indiscipline can sometimes bring their party to life and lead to constructive policy positions, such as in relation to the UK's non-membership of the euro.

Nonetheless, united parties tend to win elections. Albeit with a slippery grip, Labour still wields the weapons of superficial unity and loyalty previously owned by the Conservatives. As with Labour in the 20th century, parts of the Conservative Party do not seem especially attracted to these weapons, let alone interested in using them.

s.richards@independent.co.uk; twitter.com/@steverichards14