It was unprecedented straight talk from an assemblyman, something one rarely sees in Vietnam. And it is further confirmation that Vietnam's political development has entered an extraordinary, if indeterminate, phase.

At the root of the crisis is a confidence gap between various increasingly vocal elements within the state apparatus and defenders of an increasingly untenable status quo, of which the prime minster is the most emblematic.

Last week's drama was only the latest in a string of recent developments that have severely weakened Dung's stature.

For years, Dung has taken heat for major corruption scandals, soft credit, mountains of bad debt and crashing state-owned businesses, while policies associated with him have been blamed for surging inflation, declining foreign investment, and stagnation or real declines in living standards.

The last six weeks have not been kind to Dung. In October, at Vietnam's Sixth Plenum of the Party Central Committee, the secretive Politburo formally announced a readiness to censure Dung, only to be rebuffed by the Central Committee, which insisted the Politburo reflect on its collective shortcomings instead.

This in turn prompted the prime minister to offer a public apology of a sort not seen since the 1950s. Dung has since been replaced by General Secretary Nguyen Phu Trong as head of the national anti-corruption body, while his portfolio of oversight positions in state-owned conglomerates has been nearly halved.

In the meantime, a critical mass has coalesced within the state apparatus, on its borders and in cyberspace, around the perception that poor leadership and governance are truly endangering Vietnam's prospects for the medium and longer term. It would be no exaggeration to state that the Communist Party of Vietnam is facing its most severe leadership crisis since the aftermath of land reforms in the late 1950s.

In this context, it is perhaps fitting that it was Quoc, a historian by profession, who stood up to be heard. His actions remind us that although Vietnam's elite powers have historically repressed dissident voices, they do have their limits.

This episode may be a sign of hope. For only with accountable leadership will Vietnam manage to bridge its proud if difficult past to a promising future.

By Jonathan D. London - The South China Morning Post - November 20, 2012