Even his detractors had to agree that Prime Minister Narendra Modi delivered a virtuoso performance in Washington, DC. His much applauded speech to the US Congress spoke of overcoming the "hesitations of history" while cementing the partnership between two democracies. He outlined his ambitions for India, reached out to Indian Americans, threw in a few jokes, a jab at the opposition. It was a masterful performance, on all counts. But who wrote the words that he gave resounding voice to?Each of the prime minister's speeches draws on inputs from various sources - party units, ministries, subject experts, associations of overseas Indians, and his own team. Modi's speeches are a "collective achievement that still come across as uniquely individual," says social scientist Shiv Visvanathan, who has studied Modi's evolving public image. "His backroom guys deserve an Oscar for his performance too," he adds.In the US, speechwriters have been part of the presidential entourage since Franklin Delano Roosevelt. John F Kennedy , Richard Nixon, Ronald Reagan, Barack Obama have all had aides valued for their phrasemaking skills and their rapport with the boss. But in India, they are phantom presences, sensed but never seen. Politicians are loath to openly acknowledge the preparation behind their orations, and their advisors know better than to claim credit for the good lines.The role of the speechwriter varies, depending on the leader's rhetorical skills - whether they relish public speaking or see it just as a job requirement. Modi, of course, is definitely the former kind - even before he was formally declared the BJP's candidate for PM, he delivered his own thundering Independence Day address in 2013, saying the country would compare his speech with that of Manmohan Singh 's.Singh himself was not a natural speaker, but spoke regularly. Sanjaya Baru, his media advisor for over four years during UPA 1, says he wrote over 1,000 speeches in that period. Jawaharlal Nehru , famously silvertongued, spent a great amount of time writing his own speeches, relying only reluctantly on others. But most prime ministers since have seen the need for professional speechwriters and press advisors, usually former journalists. H Y Sharada Prasad had the capacity of knowing what Indira Gandhi wanted to say, becoming her alter ego, giving voice to her own thoughts."There are two models of speechwriting for the PM. One, where they sit and talk to you about what they want to say, which is usually for important occasions like Independence Day, important international forums and so on. Then there are the routine speeches at Vigyan Bhawan, the launch of an infrastructure project, or other regular addresses," says Baru.For the more mundane events, the speechwriter takes the lead, collecting inputs from various ministries and departments. When it comes to political speeches, party officials provide talking points. Baru started the practice of reaching out to experts, consulting academics like Sunil Khilnani or journalists like Fareed Zakaria, even though government insiders like Mani Dixit bristled at the innovation. All memorable speeches go through various iterations, no matter how inevitable and natural the words finally sound.A good leader, though, puts his or her own stamp on the speech. "The PMO is very well equipped to get the right inputs from everywhere, on varied subjects," says Sudheendra Kulkarni, who wrote speeches for Atal Bihari Vajpayee . "But of course, the PM gave ideas, direction, and corrected drafts of the speech," he says.Rajiv Gandhi, too, was "very involved with the writing, and was part of the process" says one of his speechwriters. Even Manmohan Singh wanted some literary flourishes. "When I was writing a speech on the loan waiver, he recited a few lines from Oliver Goldsmith, about how vital peasants were to the country, and asked me to weave them in," says Baru.Vajpayee was known for his oratory, but actually sought a certain restraint as prime minister, says Kulkarni. "He was aware of the weight of his speeches, and wanted every statement to be incontrovertible, every fact checked and cross-checked," he says. He gently told a cabinet minister from Madhya Pradesh, known for his flights of poetic fancy "mantriji, sarkar chalana kavita likhna nahin hai", recalls Kulkarni. And because he had a natural flair for speeches, he could correct himself mid-way.Once, addressing Indians abroad, he called himself a swayamsevak, and amended that to "rashtra ka swayamsevak", with nobody picking it up to make it a controversy, says Kulkarni. Though he put careful preparation into every speech, including parliament interventions, many of his most famous moments, like the "insaaniyat ke daayre mein" speech in Kashmir, were spontaneous, says Kulkarni.All speechwriters note that a speech is not mere flat words on a page, however eloquent. Rhetoric is the art of audience-pleasing and audience-moulding. Modi's speeches rely on extensive polling, to identify issues that resonate, lines that will move the crowd. He also knows how to sprinkle media-friendly soundbites and punchlines.A speech has to work with the assumptions with its listeners. Narasimha Rao , for instance, who did not have a full-time writer because he trusted himself more, delivered a speech to the All India Congress Committee session in 1992, where he made a break from Nehruvian economic, foreign and social policy, even as he quoted Nehru extensively. He consciously "used Nehru to undo Nehru", says Baru.Part performance, part literary effort, always a political instrument - the prime minister's speeches set the tone of the government. And the anonymous scribblers who played a part may not get direct credit, but they know the worth of their words.