MR JATUPORN Promphan's taking over as chairman of the United Front for Democracy against Dictatorship (UDD) signals a more assertive pro-government "red shirt" movement, analysts said.
The UDD is an umbrella group for the red shirts. The relatively hardline Mr Jatuporn on Saturday replaced the conservative Ms Thida Tawornseth, whose term has ended.
The change comes amid a grinding and volatile political stand-off, pitting the red shirts against the People's Democratic Reform Committee (PDRC), which is trying to paralyse Prime Minister Yingluck Shinawatra's government and drive it out of office.
The government has its back to the wall. The country has been left with an incomplete snap general election disrupted by the PDRC, no sitting Parliament, and multiple legal challenges to the legitimacy of the government and Ms Yingluck. The Premier is a proxy target for her brother, ex-premier Thaksin Shinawatra who is said to be directing the ruling Puea Thai party from abroad.
UDD leaders believe Ms Yingluck's government is bound to be brought down, most likely in a "judicial coup", or court judgments against it.
One such judgment, due in less than a fortnight, could see Ms Yingluck suspended for negligence in allowing a populist rice purchase scheme that has led to huge stockpiles of unsold Thai rice as well as questions about corruption.
The red shirts view the courts as instruments of the establishment elites - backers of the PDRC - and are organising to resist the removal of the government.
Some leaders are signing up volunteers to "protect democracy" and militant factions are becoming impatient, sources said. "The next battle will be big," Mr Jatuporn told Associated Press news agency yesterday.
While he advocates non-violence like Ms Thida, he is seen as more aggressive and better able to take on PDRC leader and veteran politician Suthep Thaugsuban, with whom he has crossed swords often in fiery parliamentary debates.
"Jatuporn will be more assertive. He will be a better foil against PDRC leader Suthep Thaugsuban," said political science professor Pitch Pongsawat from Chulalongkorn University.
Mr Jatuporn has been a key mobiliser and firebrand speaker, and spent time in jail for his part in the 2010 violent protests of the red shirts.
But even Ms Thida is taking a hard line this time. On Saturday, she said: "The way to fight via the parliamentary system is now closed. Now, we will fight to the end and we will not lose."
Said Prof Pitch: "As long as the red shirts don't march into the city of Bangkok, there won't be a physical clash. But we can't deny there will be a rhetorical war."
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