His achievement in stitching together the India-US civil nuclear deal and successfully overcoming domestic resistance to it, including from his own party boss, is chronicled in "The Accidental Prime Minister: The Making and Unmaking of Manmohan Singh" (Penguin) that hit the stands over the weekend.
While trying to get the support needed for the India-US civil nuclear deal, Manmohan Singh was "left to his own devices and he made sure he had his way," the book said.
"He cajoled the nuclear establishment into falling in line. He pushed, then national security adviser M. K. Narayanan, to seal the deal. He ignored the doubters in the external affairs ministry and empowered the believers."
"He convinced President Bush that backing the deal, at home and abroad, was in America's interest too. He went to Trombay and addressed scientists. He went to Washington DC and addressed Congress. He reached out to China and Pakistan, softening their resistance. He spoke repeatedly in Parliament, at length and emphatically, and courted public opinion," the book noted.
Faced with the threat of his resignation if the party failed to support him on the nuclear deal, Sonia buckled. "There was no one else in the party who had his qualities of competence and compliance. She was certainly not prepared to name Pranab Mukherjee as prime minister or even as deputy prime minister."
Early on in his tenure when Manmohan Singh realised he would not be allowed free run in matters of governance, due to pulls and pressures of the Congress party and allies, he "decided that foreign policy was one area where he would be the boss".
Manmohan is said to have retained his influence over economic policy.
"He mostly conceded limits to his authority in shaping domestic policy, given that his council of ministers had loyalties to other centres of political power. But he jealously guarded the foreign policy turf and ensured his writ would run at least in this sphere."
Manmohan Singh "retained his influence over economic policy through Chidambaram and Montek. But foreign affairs was his sole preserve and he made sure it stayed that way in UPA-1. It was the area where he could articulate his vision for India in a changing world, and project his personality, without coming into conflict with the priorities and the profile of the Congress president," Baru wrote.
Baru said an attempt by him to give the prime minister credit for the National Rural Employment Guarantee Act (NREGA) scheme, which had been brought out by the Prime Minister's Office, was not liked by the Congress high command. The party was projecting it as an achievment of Rahul Gandhi and Baru's SMS to an editor "half in jest" that it was the PM's birthday gift to the nation fetched him an admonition from the prime minister.
"Let them take all the credit. I don't need it. I am only doing my work. You just write my speeches for me. I do not want any media projection," Manmohan Singh said, according to the book.
Baru said, "Dr Singh had a powerful story to tell about his achievements as prime minister, but he invariably shied away from telling it. He held me back when I sought to project him during my time as his media adviser, saying, 'I want my work to speak for me.' Perhaps Dr Singh was nervous about projecting himself because he thought that was the undoing of P.V. Narasimha Rao".
Manmohan Sigh consciously strove not to project himself. "His problem always was that he did not want to become more popular with the media and the general public than Sonia. Whenever a TV channel or newsmagazine conducted an opinion poll and showed that his popularity, while rising, was a few notches below that of Sonia, he would feel relieved. 'Good,' he would say, with a mischievous smile. That defined the limit to his projection and brand-building," Baru felt.
Baru says that Prime Minister Manmohan Singh, whose decade-old tenure at the country's helm ends next month, has shown the country "that an ordinary, honest Indian, an aam aadmi, to use the current buzzword in politics, could become prime minister through sheer hard work and professional commitment."