Pavin Chachavalpongpun is associate professor at Kyoto University and currently a fellow at the University of California, Berkeley.

The magical reign of King Bhumibol Adulyadej has ended.

The Thai king, and world’s longest-reigning monarch, passed away on October 13, at the age of 88. The king served as the symbol of Thai unity and stability; his departure has left a gigantic hole in the Thai political landscape that is now filled with uncertainties over the future of the country without the charismatic king.

Born in 1927 and crowned in 1946, King Bhumibol led an authoritative reign that competed fiercely with civilian governments for political power and the loyalty of the Thai people. The king was made into a sacred and inviolable entity, protected by the harsh lèse-majesté law which states that insulting comments against the monarch would be sentenced up to 15 years. Yet, his godly image did not prevent him from performing as the people’s king. His royal development projects were implemented to improve the livelihood of countless Thais. To them, the king meant everything.

After announcing the death of King Bhumibol on national television, Prime Minister Prayuth Chan-ocha  confirmed that Crown Prince Maha Vajiralongkorn would succeed the throne as King Rama X. The announcement was met with with a great sense of anxiety as many fear that Vajiralongkorn may not be able to provide the kind of stability his father did.

Crown Prince Vajiralongkorn will face serious challenges should he seek to follow in the footsteps of the late king without his father’s necessary qualities.  He does not enjoy the same love and respect from the public that his father commanded. He lacks Bhumibol’s moral authority and charisma; the overwhelming attention on Bhumibol long eclipsed Vajiralongkorn. Vajiralongkorn has shown little to no enthusiasm for working with democratic institutions or being a democratic advocate. He has enjoyed his eccentric and lavish lifestyle, with no one daring to inspect his spending of taxpayers’ money. He has dealt with his enemies ruthlessly. One of his confidants, a famous fortune-teller named Suriyan “Moh Yong” Sucharitpolwongse, died mysteriously while under detention. Suriyan was accused of exploiting the name of the crown prince for his own benefits.

With a weaker prince now on his way to becoming king, it is possible that the military could become the ultimate arbiter in Thai politics.

During his reign, Bhumibol built an alliance with the military, creating a “network monarchy” which placed the royal institution at the apex of the Thai political structure. Together, the monarchy and the military designed a political system whereby elected governments would be kept weak and vulnerable. Should elected civilian rulers pose a challenge, they would be toppled in military coups.

But the uncertainty surrounding Vaijralongkorn and his ability to provide security to those in the network monarchy drove the military to interfere in politics as evidenced in the 2014 coup, when the army attempted to take control of the royal succession.

Realizing the importance of the military as a key partner of the monarchy, Vajiralongkorn has forged his own relationship with the current military government. In the aftermath of the 2014 coup, the crown prince presided over the military-appointed legislative council, praising the army for ensuring peace and order in the country.

But the new alliance between the military and Vajiralongkorn could seriously impact Thailand’s democracy. Under King Bhumibol, the monarchy never operated within the constitution, a configuration that the people gradually accepted as a part of Thai political culture.

Vajiralongkorn’s alliance with the military may explain why the royal transition is likely to be trouble-free, at least in the short run. After all, the entire nation is supposed to fall into a state of endless mourning. Thais have been told to wear black for a year. Long months of grieving may delay any public discontentment regarding the king-in-waiting. It may also help legitimize Vajiralongkorn’s controversial accession to the throne.

In the long run, the poor performance of Vajiralongkorn could stir up a greater sense of anti-monarchy in the kingdom. Some in the red-shirt camp, supporters of former prime minister Thaksin Shinawatra, have already flirted with the idea of republicanism. They see an end of the royal institution in Thailand; Vajiralongkorn represents the failure of the constitutional monarchy model. Even within the royalist faction, the choice of Vajiralongkorn is a let-down. They preferred his popular sister, Princess Maka Chakri Sirindhorn, as monarch. But the constitution constrains a female heir.

As for Vajiralongkorn, the path ahead is clear. If he chooses to maintain his alliance with the military and refuses to work with democratic governments, his reign will be contested and may not survive. If he decides to go ahead with reform, placing the monarchical institution strictly within the constitutional framework, the chance of the monarchy becoming a viable institution is bright. Vajiralongkorn needs to make this tough decision. The future of his reign depends on it.