A popular economics professor at the University of Buenos Aires, Kicillof always stood out for "his brilliance, the eloquence and simplicity with which he's capable of transmitting complex ideas, and his determination and honesty when it comes time to take action," said his friend Sebastian Rubin.
With penetrating blue eyes and Elvis Presley-style sideburns, he seems years younger than his age, and refuses to wear a suit or tie even in rooms full of dignitaries. But he's audacious enough to dictate terms to executives of the world's biggest oil companies. And he should be watched closely for clues about what Fernandez may do next, analysts say.
"The government of Cristina is so personalized that everyone is trying to figure out who this new confidant of hers is," said Mariel Fornoni, a consultant with the Management & Fit firm in Buenos Aires.
In his Senate testimony, Kicillof scoffed at the claim that investors might shun Argentina due to a lack of "legal security," calling them "horrible words" and saying that record investment has flowed into Argentina.
"What better rule of law, what better business climate, than a government committed to continued growth, to sustaining internal demand, to sustaining our extraordinary exports to the rest of the world?" he said.
When he finally handed over the microphone, it seemed as if there was no air left in the room.
Now his arguments are enshrined in a law that puts Argentina's entire energy industry under the threat of state intervention. It declares energy self-sufficiency to be a public good and a top national priority, and says any company working to develop, market, ship or sell oil or gas in Argentina must first ensure that the growing economy gets all the energy it needs at controlled prices before exporting oil or gas for much higher prices on the world market.
The same argument could apply to a range of other privatized state companies, from telephone providers to toll road operators, analysts say.
"I don't know how far Cristina thinks Kicillof ought to continue in politics, nor whether he wants to do it," consultant Ricardo Rouvier noted. "But he's a young guy with great potential."
Associated Press Writer Almudena Calatrava contributed to this report.
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