There is a view — held by some commentators on both sides of the Atlantic — that Britain’s initial refusal to allow American forces to use its bases for strikes on Iran was not a failure but a statement of principle. The argument is that democratic governments should not be compelled to participate in military operations they have not independently assessed and endorsed.
On this reading, the prime minister’s hesitation was not a failure of nerve or an act of political cowardice, but an exercise of the kind of independent judgment that sovereign governments are supposed to make. The fact that the decision was made in the face of pressure from a powerful ally makes it, on this view, more admirable rather than less.
The counter-argument — pressed with some force by the American president and the secretary of state — is that alliances are built on mutual obligation, and that failing to honour those obligations when the moment of need arrives undermines the foundations of the partnership. A fair-weather ally, on this view, is not really an ally at all.
Britain’s eventual decision to grant limited access — framed as defensive and in the national interest — was an attempt to reconcile these competing positions. It acknowledged the obligation of alliance while maintaining a distinction between participation and co-belligerency.
Whether that distinction was meaningful in practice — and whether it was sufficient to repair the relationship with Washington — was the central question that the episode left unresolved.