Thailand, the land of politeness and smiles, is also famous for kickboxing. The street battles in Bangkok this week were a window into the country’s pugilistic side, an outpouring of frustration by protesters who say they feel injustice and discrimination in the workings of Thailand’s troubled democracy.

Although the protests ended peacefully Tuesday, the grass-roots resentment and anger are likely to linger.

“Whoever wins or loses this round, the stalemate and tension will remain,” said Thongchai Winichakul, a professor of Southeast Asian history at the University of Wisconsin.

The “red shirts,” as the protesters are known, draw their strength from the north and northeastern parts of Thailand. Many of them are farmers and small businessmen, and they portray themselves as battling an unelected but influential elite, notably the judiciary, the military and the powerful advisers of King Bhumibol Adulyadej.

A central lament of the red shirts is that the will of the electorate has been repeatedly thwarted: three prime ministers since 2006 have been forced from office — one in the military coup of 2006 and two removed by the courts in highly political trials.

“They chased out governments that were elected,” said Thongdee Wongsamart, a middle-aged protester who recently lost her job as a cleaner in a tour company. “I’m angry.”

Many of the red shirts are followers of Thaksin Shinawatra, the former prime minister ousted in the 2006 coup. But they are often quick to point out that their grievances about the state of Thai democracy are more important than their support for Mr. Thaksin, a former telecommunications tycoon.

“This is not only about Thaksin and his money,” said Mr. Thongchai, of the University of Wisconsin. “These are people against the coup who are targeting an unelected bureaucratic elite.”

Many red shirts say they do not trust the Thai media, which they accuse of siding with the government. Those from the provinces say they resent being looked down on as people who speak funny dialects. They draw the contrast between the light touch used by security forces last year against royalist protesters and the thousands of troops who forcibly dislodged the red shirts from Bangkok’s streets this week.

The royalists crippled the country late last year by blockading Bangkok’s two commercial airports for a week, stranding hundreds of thousands of foreign visitors. They surrounded Parliament and trapped legislators inside, receiving moral support from the king’s wife, Queen Sirikit.

“This country has a double standard, has no justice and will never be peaceful,” read a comment on pantip.com, an Internet chat site that has a popular political section. “There will be civil war because people see that injustice has become an acceptable thing.”

The royalists are seen as having an invisible hand protecting them.

“I don’t understand why the army did nothing when the PAD seized the airports,” said a user on pantip.com, referring to the royalist People’s Alliance for Democracy. The leaders of the royalist protests were eventually arrested but then quickly released on bail.

The case against the group “has not proceeded very far and it appears that its leaders may eventually be indicted with lesser charges, if at all,” David Streckfuss, an expert in Thai politics, wrote in The Bangkok Post on Tuesday.

The government has closed down several Internet sites linked to the red shirts as well as a satellite television station that carried live broadcasts of the protests. By contrast ASTV, a satellite station run by a royalist, Sondhi Limthongkul, was never shut down. While he was still in power, Mr. Thaksin sought to keep Mr. Sondhi off the airwaves. The red shirts gloss over this side of the former prime minister.

But he often mixed his personal business interests with those of the government. He intimidated journalists. And his crackdown on drugs may have came at the cost of what human rights groups say were hundreds of extrajudicial killings.

“Thaksin is a minor point in my opinion, and the major point is democracy,” said Somchai Luangtant, 49, who sells graduation gowns in Bangkok. “People should know that the Thai people want real democracy, not like what we have right now.”

Seth Mydans contributed reporting.