Mr Cameron, it must be said, is no slouch: in announcing that sanctions on Burma are to be not lifted but "suspended", he succeeded in saving everyone's face while at the same time throwing almost everyone off balance.
This was not on the cards. Harmless, merely humiliating or vexatious measures, it was expected, would be removed at a stroke, while those that stop evil, bloodsucking warmongers from climbing into bed with captains of British industry were to be retained – at least until Burma was a slightly more plausible democracy. At that point, perhaps with the National League for Democracy in power and President Suu's face on the banknotes, they, too, could go.
But heaven won't wait. Mr Cameron has used his whistlestop tour of Burma to change the sanctions game for good.
All sanctions – except, "obviously", as he put it, those banning arms sales – are to be suspended. All the UK businesses that have dreamed of digging out Burmese jade or removing oil and gas or teak and ebony, or setting up trainer-making sweatshops to undercut those of Cambodia, need dream no more. At the end of the month, at its annual deliberation on what to do about Burma, the European Union will back the Cameron plan, and the scramble can begin.
But then what? If the sanctions are only "suspended", when might they be reimposed? Are there to be no benchmarks at all? What about the corruption, the child soldiers, the theft of land, the war still fomenting in the far north? The answer will be a Europe-wide shrug: we do lots of questionable things in lots of questionable places already. Burma can join our club.
But what does it do for Aung San Suu Kyi?
"I support the idea of suspension," she said, adding that if those against reform refuse to play ball, "then sanctions could come back".
But this is a tricky transition for Ms Suu Kyi, the newly elected MP for Kawhmu. Under unprecedented pressure from the regime and her international friends, Suu Kyi has been forced to take her party out on a limb. She has gambled everything on President Thein Sein staying the course and backing her plans for change to the Constitution. Perhaps she had no choice in the matter, but if the process fails and Burma slides back into its bad old ways, the big losers will be Suu Kyi and her party.
Peter Popham is the author of The Lady and the Peacock: The Life of Aung San Suu Kyi