MAE SOT, Thailand — The lightning-fast pace of reforms in Burma has so far included the release of hundreds of political prisoners, renewed ties with the US and an end to the world’s longest-running civil war.

Not so long ago, each measure would have been nearly unthinkable and yet, today, reforms are unfolding at quite a clip. Or are they?

Some measures, like the release of prisoners, are tangible and swift. Others, like an end to the conflict between Burma’s Thein Sein government and the Karen National Union (KNU), an ethnic rebel group that has been fighting for autonomy for more than 60 years, will take months to solidify.

And many are skeptical whether that will, in fact, happen.

The decades-long conflict between the Karen, who number as many as 7 million, and the government has resulted in countless military atrocities, according to human-rights groups. Rape, forced labor and child conscription succeeded in driving hundreds of thousands of Karen refugees across the border into Thailand.

KNU Vice President David Tharckabaw joined the Karen National Liberation Army, the armed wing of the KNU, as a soldier at the age of 14. He is now in his late 70s and spends most of his time living in exile.

“It’s very difficult to trust people that have been killing, displacing, and abusing your people for over 60-years,” Tharckabaw said in August 2010, during a private meeting over tea in the living room of his exiled safe house near the Thai-Burmese border.

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“Without a federal solution, I don’t think there can ever be peace and stability. The ethnic minorities simply don’t trust them,” he said.

Yet, flash forward 16 months. KNU and government representatives sat together at a table last week in Pa-an, capital of the Karen state. They shook hands and agreed on terms and conditions for peace.

The next day, Burma released 651 prisoners, in what is being called the largest single release of political prisoners in Asia’s history.

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The United States responded by renewing diplomatic relations with the country and declaring the intention to reinstall an ambassador.

The US and the European Union stopped short of lifting sanctions, but it seems increasingly likely that the economy will open soon. Most of the reforms that have taken place — including an end to war against ethnic minority groups and a release of political prisoners — were all stated as preconditions to the lifting of US and EU sanctions.

Tharckabaw, KNU vice president, agreed to a telephone interview over the weekend to discuss the events that precipitated the once unthinkable cease-fire as well as how trustworthy he thinks the regime is when it comes to promises of progress.

How did change come about?

“We felt that there are positive changes taking place that leave room for cautious optimism. Although it’s more caution than optimism,” said Tharckabaw.

“The international community is dangling bigger carrots than ever before to push Thein Sein’s government to reform," he added.

Among the other recent reforms: Burma's government has lessened restrictions on freedom of association, legalized the right to peaceful demonstration and said it would allow opposition leader Aung San Suu Kyi to participate in the upcoming by-elections.

“When Suu Kyi decided to participate within the framework set by the current regime, it showed that she feels there is a decent probability for change. That gave us a lot of confidence that maybe this time the government's intentions are real,” said Tharckabaw.

The government offered peace talks with all ethnic minority groups, including the Karen, in a statement on Aug. 18 of last year. After lengthy consultations with Karen followers overseas and inside Burma, and an intense two-day deliberation the KNU leadership decided upon an 11-point demand of terms of conditions for the cease-fire.

“Our critical demands were that the government agree to stop all military offensives in the Karen territories, release all political prisoners, and allow the Karen people to move about freely and without hindrance within the Karen state,” said Tharckabaw.

Tharckabaw said that the KNU will issue a statement soon with the full list of terms and conditions agreed upon at the cease-fire.

More cautious than optimistic

The cease-fire with the KNU is being touted by the government and many in the international media as a major breakthrough, but many Karen in exile are still wary about buying in to the hype.

“The cease-fire was only the first step. I’m nervous about getting through the next stages because both parties have had such a bad history,” says Tha Wah, a 26-year old Karen refugee who left his parents in Burma and crossed the border into Thailand’s Mae La refugee camp as a young teenager.

Tharckabaw says that until the cease-fire proves to be valid and durable, the KNLA will not relinquish arms nor will the KNU begin telling the thousands of Karen refugees in exile that it is safe to return.

“This is not a surrender, nor is it peace. They’ve agreed to our principles so we’ll continue to talk to them. Talking is good, it’s better than fighting. But if we come under attack, believe me, we will fight back,” said Tharckabaw.

Twenty-six of the 30 ministers appointed to Burma’s executive cabinet are former military officers, and many feel that it’s still unclear what the true intentions are of those in the capital Napyidaw, or even who is really in control.

The army has launched a major offensive in the northern Kachin state, where fighting since June has displaced tens of thousands of people, despite President Thein Sein’s call for a halt to all military action on Dec. 10, 2011.

“We believe Thein Sein when he calls for peace. But it seems like there are divisions on that side between the political leadership and the army because the army isn’t listening to him,” said Tharckabaw.

“They could very well do the same to us. We need to continue to see positive developments in the political dialogue over the next five to six months before a peaceful solution will begin to truly look viable.”

For the Karen, despite all the progress the last 16 months have seen, the next 16 months may prove to be the most critical of all.