One of the main reasons I am so drawn to Hitchcock is that he planned his shots way in advance on story-boards which he designed like classic paintings (he was an art connoisseur). It's why he found shooting on set boring - because he had already composed the film in his head.
In the final analysis the incident is seen as originating from an emotional expression of the frustration and anger of the proud people of China who had been subject to ever increasing oppression from without and decadent corruption from within.
