In it, Giordani launched a series of scathing criticisms of the "new path" he says the government has taken since former president Hugo Chavez died in March last year.
Giordani dropped the bombshell on June 18, a day after he was removed from the post he had held almost uninterruptedly since 1999.
Many view Giordani as a principal architect of the Chavez government's economic policy and representative of a more orthodox Marxist strand within cabinet. His removal has been pointed to as evidence of a widening rift within the Venezuelan government.
Giordani's letter has also had the effect of blasting the lid off a debate that had been largely simmering below the surface.
Some hope that this discussion will feed into the upcoming congress of the governing United Socialist Party of Venezuela (PSUV).
Despite the fact that almost half of conference delegates are not elected by the party's rank-and-file, grassroots activists are organising to ensure their presence is felt at the congress.
However, attempts by some sectors in the party to silence dissent have cast doubts over the PSUV's future.
An increasingly public dispute among PSUV leaders has involved denunciations of creeping "Stalinism" within the government. Others have countered with accusations that every revolution "has had its Trotsky". This is a reference to the historic dispute in the Russian Revolution between Josef Stalin and Leon Trotsky after Vladimir Lenin's death.
That clash was resolved through Stalin's brutal suppression of debate, which included the exile and assassination of Trotsky as well many other opponents.
Public letter and responses
In his letter, entitled "Testimony and responsibility in front of history", Giordani directly criticised what he said was President Nicolas Maduro's inability to project clear leadership, arguing this had generated the "sensation" of a "power vacuum".
He said private business sectors had successfully prodded the Maduro government towards implementing economic reforms that "would facilitate [their] attempts to recapture oil wealth".
Giordani outlined some recommendations he made while still in Maduro's cabinet. These focused on combating corruption and greater control over public funding. He said these were largely ignored.
He said he hoped the letter could help "revive", within the revolution, "mechanisms for the confrontation of ideas and joint work, under a leadership respected by all".
Giordani's document provoked a flurry of responses. Many noted that while Giordani had been quick to point the finger at others for the country's economic problems, he seemed to absolve himself of all responsibility.
This was despite having been a key figure in the government's economic policy.
Rodolfo Sanz, a former Chavez minister, questioned the motivation behind Giordani's public criticism. "It is not unheard of," he wrote, "for people who have held important responsibilities. within the Bolivarian Revolution, to open fire against the process on leaving their post."
Far from being part of the "frank and constructive debate that must exist among true revolutionaries", Sanz accused Giordani of simply attacking those who continued to advance the revolution.
Maduro himself appeared to publicly question Giordani's motivations during a televised cabinet meeting on June 19. Although he did not mention Giordani by name, many believe that his statement regarding disloyalty as akin to betrayal was a direct reference to the former minister.
Some comrades, said Maduro, prefer to stay in the rearguard "and become chroniclers of failure", rather than realise that "people are the heart of the revolution".
Defending his record in government, he said he had always acted in favour of the people, "not for the bourgeoisie or for technocrats who think they are superior to the humble folk".
Others welcomed Giordani's letter, even if they did not completely agree with its form or content. The Simon Bolivar Collective noted that, despite their disagreement with Giordani's general political outlook, he could not be labelled a traitor.
They said his criticism was necessary, even if "mistimed".
PSUV members Toby Valderrama and Antonio Aponte, who publish a widely read newspaper column, warned against dismissing Giordani's accusations. "[When] a key cadre like Giordani raises an alert," they wrote, "the Revolution, and above all its leadership, is obliged to reflect."
Several high-profile PSUV leaders and former ministers also called for respect for differences and for the government and party to treat Giordani's statements seriously.
PSUV national executive member Freddy Bernal wrote an article on the popular pro-revolution website Aporrea noting that revolutionary unity required "criticism and self-criticism".
Rather than divide the movement, debates helped to "tweak unity, correct the path in case of deviations and accelerate the march towards socialism".
On June 24, former minister and PSUV national executive member Hector Navarro published a letter on Aporrea recalling how Giordani had tried on several occasions to raise his concerns in private with Maduro and PSUV leaders.
He also referred to Giordani's exposure in 2012 of US$20 billion that had been illegally acquired through the existing currency regime.
Navarro asked: "Is Giordani the traitor? Or are the traitors, even if no one talks about it, those who assigned dollars that today are needed by our hospitals, or are necessary to boost production and to meet the needs of the people?"
Later that day, Navarro published another letter revealing he had been called up to face the PSUV's disciplinary tribunal.
This provoked the ire of another former minister and PSUV national executive member Ana Elisa Osorio, who tweeted "two of Chavez's most loyal comrades suspended and called traitors. Something bad is happening in the PSUV."
Another former minister, Victor Alvarez, denounced the move as "pure and simple Stalinism".
Maduro responded at a June 25 public rally. Ratcheting up the heat, he referred to "vacillating petty bourgeois" sectors and "disloyal ex-ministers who didn't do things as they should have."
"They are very inconsiderate, these enemies of the left. History will judge them."
Various other government and PSUV leaders made similar comments over the next few days. Speaking to an assembly of party militants, the PSUV first vice-president Diosdado Cabello criticised revolutionaries that "instead of using their energy to criticise the right, criticise President Nicolas Maduro. Is criticism more important than loyalty?"
He warned that the party had rules "and we will make sure they are implemented".
PSUV governor Francisco Ameliach used his weekly radio program to state: "We can't let a few individuals generate fissures in our party."
Bernal, on the other hand, said Navarro and Giordani would be given a chance to express their views at a meeting with PSUV leaders.
With discontent over the handling of the debate spreading through the party, Maduro used a June 30 speech to publicly extend an olive branch to those he had so harshly criticised just days before.
Maduro said these differences with comrades who are "without a doubt revolutionaries and Chavistas" had to be dealt with in a manner that could facilitate a "reunification".
Later that day, he asked everyone to "turn the page" on the saga of tit-for-tat letters and statements. "We have said everything we had to say. Now, the hand is extended and the embrace is ready to be given to all comrades."
However, as Navarro noted in a further open letter on July 12, Maduro's call for dialogue largely fell on deaf ears.
No meeting to discuss the differences was called, the demand to face the disciplinary tribunal remained and "name-calling persists in speeches by some [PSUV] leaders".
Navarro drew particular attention to statements by Ramon Rodriguez Chacin, the coordinator of the PSUV disciplinary tribunal. Chacin publicly said that every revolution "has had its Trotsky".
Apart from questioning the right of the head of the tribunal to condemn him as guilty without a fair trial, Navarro asked: "If according to Rodriguez Chacin I am Trotsky, is he suggesting that Comrade Nicolas Maduro is a Stalin, thereby agreeing with the enemy?
"Furthermore, is Rodriguez Chacin suggesting for me a fate similar to Trotsky?"
Navarro drew attention to serious problems in the democratic functioning of the party. According to him, the PSUV national executive hardly met over the past year. It had essentially been replaced by a High Political Command composed of government ministers and top party officials.
The party's leadership bodies at almost all levels were not functioning, Navarro said. "The [internal] spaces in which true collective discussions can be held about government and party-related problems are diminishing."
Roberto Lopez Sanchez, a trade union leader and PSUV militant, raised similar concerns. He wrote: "Today, more than 18 months after [the High Political Command] was created, we do not know if it is part of the state structure or if it is a 'super-leadership' over and above the PSUV national leadership."
He denounced the undemocratic nature of this unelected, seemingly "all-powerful" body, and said any deepening of the revolution was predicated on a return to the original, participatory spirit that Chavez had imbued in the process.
A newly elected PSUV leadership should replace the unelected High Political Command, he argued.
With the PSUV's third congress fast approaching, it is evident that a fierce debate has opened up in the party. For the first time, party leaders are publicly taking opposing sides.
Going beyond "Stalin-Trotsky" analogies, it appears that two positions have emerged.
Some have pointed to divisions between "radicals" and "pragmatists" ― or "the grassroots" and "the bureaucracy". However, it appears that the key division is between those who condemn public criticism as disloyal to the leadership and those who see peoples' active participation and criticism as the heart of the revolutionary process.
Pragmatists and radicals can be found on both sides of this debate, as can party leaders and rank-and-file members.
The fact that almost half of the congress floor will be made up of unelected delegates holding public posts (mayors, governors, parliamentarians etc) will no doubt have a big impact on the outcome of the congress.
PSUV leaders have also announced that a new party leadership will not be elected at this congress.
Both issues demonstrate how far the PSUV has drifted way from Chavez's original plans for the party when he first called for it to be built in early 2007.
In the speech where he first proposed creating a new party, Chavez blasted the idea of designating representatives from above.
He said: "This should all be done from below, from the base. The people should make these decisions, as has been written in our constitution for seven years, except we haven't done it.
"Now is the time to start."
He also called for "new faces and leaders", saying anything else "would be a deception".
Importantly, Chavez argued that grassroots and participatory democracy was vital to ensuring that the party became "a political instrument at the service not of blocs or groupings but of the people and the Revolution, at the service of socialism".
The new party had to be different from the Russian Bolshevik party, which after Lenin's death "ended up as an anti-democratic party," he said.
Chavez envisaged a party that would not only pose a threat to the capitalist class but also to those who preferred to use positions of power for personal gain. It could prove a space for the people to take control over the destiny of the process.
The PSUV never became the party Chavez wanted during his lifetime, but its former leader showed he was able to use his authority to maintain unity among competing currents while also encouraging greater grassroots empowerment.
Maduro now faces a critical test as to whether he can follow the same path ― and in the process help put the PSUV back on its original course.
[This is the second article of a two-part series dealing with the fall-out following Giordani's sacking and subsequent open letter. The first "Venezuela: Pragmatists vs. radicals?" focused on the debate surrounding economic policy.]