All eyes are on whether the new Defence Minister, Sutin Klungsang, can manage to work productively with the military to ensure stability for the Pheu Thai-led coalition government.
A civilian overseeing military affairs, Mr Sutin will have to deal with several challenges lying ahead such as military reform, the southern unrest as well as military relations with other countries in the region.
Civilian oversees military
Mr Sutin is the first civilian to take the post of defence minister who does not concurrently serve as prime minister.
Former defence ministers who were civilians and also served as prime minister are MR Seni Pramoj, Chuan Leekpai, Samak Sundaravej, Somchai Wongsawat and Yingluck Shinawatra.
Observers noted that jailed former prime minister Thaksin Shinawatra, who is widely believed to be Pheu Thai's de facto leader, wanted to ensure the military does not pose a threat to the Pheu Thai-led government and has been formulating ways to prevent future coups.
The Thaksin administration was ousted in a coup on Sept 19, 2006 before the government led by Yingluck, his younger sister, faced a similar fate in a military putsch on May 22, 2014.
The Pheu Thai-led government has now been formed, but Thaksin still has no trust in the military due to his experience of a military coup, military sources close to government affairs say.
Therefore, he was keen to promote civilian oversight of the armed forces within the new government and dampen the influence of the "three brothers in arms", the sources said.
The trio -- also known as the "Three Por" generals -- refers to former prime minister Prayut Chan-o-cha, Palang Pracharath Party (PPRP) leader and former deputy prime minister Prawit Wongsuwon and former interior minister Anupong Paojinda, along with their influence over Thai politics.
As it happens, while the PPRP and the United Thai Nation (UTN) Party are now Pheu Thai coalition allies, Gen Prawit was not offered a cabinet post while Gen Prayut resigned as a UTN member and quit politics.
Gen Vit Thephasdin Na Ayutthaya, a former chief strategist of the PPRP and Gen Prawit's close aide, and former secretary-general of the National Security Council Gen Natthapon Nakpanich, who is close to Gen Prayut, were previously tipped to serve as defence minister, the sources said.
But Mr Sutin, a Pheu Thai MP for Maha Sarakham, was eventually chosen over them.
"Pheu Thai [at Thaksin's instruction] chose Mr Sutin to show that a civilian can also run the Defence Ministry," the sources said.
However, a compromise has been reached as Gen Natthapon is expected to serve as the Defence Minister's secretary-general.
Moreover, Deputy Prime Minister Phumtham Wechayachai, another civilian, is also tipped to be put in charge of national security. Mr Phumtham, who also serves as Commerce Minister, is a close associate of Thaksin.
All eyes are also on the new government's efforts to restore peace in the deep South and who will be appointed as a replacement for Gen Wanlop Rugsanoh, head of the government's negotiation effort.
Gen Wanlop, appointed by former prime minister Gen Prayut, had to step down when the previous government left office.
Sources said Prime Minister Srettha Thavisin prefers a civilian to handle the peace process, though it is not easy to find capable and experienced individuals suited to such a specialised role.
The armed forces want a former senior military officer with experience in the region to take over.
If Mr Srettha chooses a civilian to take the job, it will confirm the government's desire to diminish the military's role and influence, the sources said.
According to Dr Prommin Lertsuridej, secretary-general of the prime minister: "There is no hidden agenda behind the appointment of a civilian as defence minister. This is in line with international practices."
Dr Prommin, who is also close to Thaksin, denied such an appointment is intended to prevent future coups, saying every Thai should join hands to prevent coups.
Prommin: No hidden agenda to appointment
The sources added that it remains to be seen whether the government will try to amend the Ministry of Defence Organisation Act BE 2551 (2008) to scrap the committee responsible for appointing military generals to pave the way for the defence minister to take over the appointment of armed forces leaders.
The committee comprises the defence forces chief, the army, navy and air force chiefs, the permanent secretary for defence, with five votes, while the defence minister and the deputy defence minister, who come from parties, have only two votes.
Currently, the Defence Minister, Mr Sutin, has no deputies so he has only one vote.
It also remains to be seen whether the government will disband the Internal Security Operations Command (Isoc) as Thaksin once did when he served as prime minister. After the 2006 coup, the disbanded Isoc was revived.
Mr Sutin has said the matter should be left to the prime minister, who is the Isoc's director, to decide.
Sutin: New defence minister has 'homework' to do
Regional challenges
Panitan Wattanayagorn, a security expert, said the new defence minister will have to grapple with many challenges ahead.
"A defence minister who does not serve as prime minister concurrently will face more challenges than his predecessors.
"He has many decisions to make on several issues domestically and abroad.
"The new minister will have to decide on how to downsize the armed forces, end military conscription, the southern unrest, and how to handle the controversial submarine procurement [that the government signed with a China concessionaire]. All these challenges are awaiting the new defence minister," Mr Panitan said.
"But there should be no major concerns at home. [Before he took office], Mr Sutin already knew the Defence Ministry is being targeted by parties for criticism.
"It should not be difficult for him to do homework and deal with the problems," Mr Panitan said.
However, he said that international and regional issues involving big power rivalries from the South China Sea to the Korean Peninsula are more difficult to handle than domestic ones, while the crisis in Myanmar was also discussed at the Asean Summit in Indonesia which ended on Thursday.
The Foreign Affairs Ministry cannot afford to support efforts to end the Myanmar crisis alone, but the Defence Ministry must also pitch in to help Thailand win international recognition, Mr Panitan said.
The defence minister will need to handle relations with the US military in a way that will benefit the country as it is necessary to keep a balance between the US and China to ensure Thailand is not drawn into taking sides, he said.
Panitan: Sutin has many key decisions to make
Wanwichit Boonprong, a political science lecturer at Rangsit University, said there are advantages in appointing a defence minister who does not serve as prime minister concurrently as he will not be seen as trying to interfere with military affairs.
Well-versed in budgets
Moreover, Mr Sutin is well-versed in the government's budget plans after sitting on a House committee on national spending.
Mr Sutin knows how the Defence Ministry's budget will be spent and the Isoc is expected to be among the first agencies the new minister will inspect, Mr Wanwichit said.
"Another challenge for the new defence minister is to replace military conscription with voluntary recruitment.
"Mr Sutin must ensure that those who sign up for voluntary recruitment receive bigger salaries than when they were conscripted as an incentive for enrolment," Mr Wanwichit said.
The draft of the government's policy statement which will be delivered to parliament tomorrow also includes a plan to make use of areas owned by military agencies to increase their commercial value and boost revenue, Mr Wanwichit said.
This will help the Defence Ministry and the armed forces to become self-reliant financially rather than depending on national budgets alone, he said.
Hospitals run by the military should admit the public to boost their income too, he added.
Wanwichit: New PM made a canny choice