"Oh we, who wished to lay for the foundations for peace and friendliness, Could never be friendly ourselves." Brecht.
It is now almost a cliché to suggest that the Conservative Party is in the process of driving the country off a cliff in an attempt to preserve the unity of their own party. The fanaticism of members of the ERG aside, it is quite a spectacle to behold the bulk of Conservative MPs, most of whom could easily get jobs elsewhere if they had to, prioritise party unity over anything else. The temptation is to see this as some kind of moral aberration explained only by sociopathic levels of self interest. But it's worth bearing in mind the remarkable human capacity to justify this self interest in moral terms.
Ruthless self promotion can always be justified morally by self belief. Once you believe your own talents are worthwhile and ultimately contribute to others, it is easy to justify self promotion as coextensive with the greater good. The same can equally be true of a political movement. And, of course, while the dangers of this pattern of thought are obvious, it is worth noting that there is nothing inherently false about this line of reasoning.
A Conservative MP might well reason along similar lines. From their perspective, the alternative to their own party being in government is a disaster. This is particularly pronounced at this moment in time, given their own beliefs about what a Corbyn government would entail. This belief may well be totally false, but the point rather is that the reasoning that follows from it is quite familiar in its form.
Moreover, from an individual perspective, the fanaticism of colleagues can easily accentuate the extent to which the maintenance of personal position is seen as necessary. I can only guess as to what goes on in Theresa May's or cabinet members' heads, but it is quite plausible they believe throwing everything else under the bus for the sake of self preservation is ultimately an act of altruism. What, they might ask, would happen, if the real fanatics took charge?
Hannah Arendt described such moral stories as a central element of totalitarian regimes. Once individual agency is taken as limited, the individual feels compelled to preserve their own position in such a system, justifying such apparent self interest with the idea that others would carry out similar tasks with less benevolence. If someone's gotta do it, it better be me. Indeed, the transgressive nature of the task at hand can merely contribute to the individual's sense of virtue. I am doing, so the reasoning goes, something I find difficult precisely because it is abhorrent, but in doing so I am ultimately serving a greater good by preventing a worse person doing the same. Because I find such a decision so difficult, I am therefore making a personal sacrifice in doing so.
Of course, the totalitarian analogy is an extreme one, and we are dealing with something dramatically less brutal. But that only serves to make this behaviour less surprising, not more so. Of course, this does not mean that such moral stories really are at work now. Perhaps we are in fact dealing with a more pedestrian variety of vanity and self interest. The problem is, the two are almost impossible to tell apart.