The role of a constitutional head of state is a tricky one. India's president doesn't have executive powers which are vested in the prime minister, but President Abdul Kalam wields power that emanates from his popularity and moral authority. So when he speaks out on something he feels strongly about, like education or communal harmony, the prime minister has to listen.

Nelson Mandela may not be the president of his country any more but he is regarded as the father of the nation in South Africa and his moral stature makes him a global leader, respected and admired everywhere and he is looked up to by other world leaders.

Among Asia's monarchs, Cambodia's King Norodom Sihanouk survived the Khmer Rouge and ensured the continuity of monarchy recently by handing over the throne to his son, Sihamoni. Even though he is no longer king, he is regarded with high respect by Cambodians.

Thailand's Bhumibol Adulyadej is the model of a people-centred constitutional monarch whose legitimacy stems not so much from tradition as the moral authority that the king commands because of his personal integrity and honour.

As I saw on a recent visit to Thailand, with his involvement in the welfare of the Thai people, he is the moral compass for the nation and has carved for himself a place in the hearts of his subjects. King Bhumibol, whose 77th birthday was celebrated last week, has the image of a reliable guardian and responsible custodian of national interest.

At a food festival organised last week at the BICC in Kathmandu on his birthday by the Thai ambassador, Penchome Incharoensak, we got a chance not just to savour Thai food that appeals to the Nepali palate, but also to look at various exhibits that showed the economic advances that Thailand has made in recent years.

There was a time when Thailand and Nepal were at similar stages of development. Like Nepal, Thailand has also battled a Maoist insurgency and beat it with the carrot-and-stick approach of military strikes and rural development. Today, Thailand has forged ahead and a lot of the credit for steering the country to the path of sustainable development and democracy goes to King Bhumibol.

The high regard that the Thai people have for their monarch is because of his simple lifestyle, personal integrity and his devotion to the welfare of his citizens. The source of King Bhumibol's power is not political or military. The public's trust in their king comes from his refusal to use political and executive power, from his moral strength and ethical standing. There is a positive lesson here for other monarchs.

Raghu Pant, a former journalist, is the Minister of Labour and Transport.