on Saturday gave a hint of what his foreign policy would look like if he is elected as the prime minister, as he advised China to "shed expansionism" and cautioned Bangladesh against demographic invasion.
"Arunachal Pradesh is an integral part of India and will always remain so. No power can snatch it from us. People of Arunachal Pradesh didn't come under pressure or fear of China," Modi told an election rally in Pasighat area of the state China claims as its own.
Modi, speaking about the contentious foreign policy issue for the first time in his election campaign, asked the neighbouring country that the "world has changed and expansionist mindset will not be acceptable". Instead, China should forge bilateral ties with India for peace, progress and prosperity of both the nations, he added.
"I swear in the name of this soil that I will never allow the state to disappear, breakdown and to bow down," Modi said.
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The nearest point on the India-China border is 35km east of Pasighat. In 2009, China had objected to the visit of Prime Minister Manmohan Singh to the state. In 2012, it again objected to defence minister AK Antony's visit, saying "it would complicate the border issue".
Pasighat was the first stop of his second poll campaign across northeast within a fortnight. Silchar in Assam and Tripura capital Agartala were the next.
"China should shed its expansionist policy and forge bilateral ties with India for peace, progress and prosperity of both the nations," said Modi.
India and China have fought a brief war in 1962 over differences on the border . China lays claim to more than 90,000 sq km disputed by New Delhi in the eastern sector of the Himalayas, while India says China occupies 38,000 square km of its territory on the Aksai Chin plateau in the west.
China has grown increasingly assertive and questioned India's claims over the territory, calling it instead South Tibet.
"Arunachal Pradesh is an integral part of India and will always remain so. No power can snatch it from us. People of Arunachal Pradesh didn't come under pressure or fear of China," he said.
"I swear in the name of this soil that I will never allow the state to disappear...breakdown and to bow down," Modi said to a thunderous applause from people gathered near the mighty Siang River.
Read: China intrudes into Arunachal, stays on for 3 days
He said China needs to change its stand.
"China should adopt the plank of development. Focus is on the development all over the world," the Gujarat chief minister said.
Modi lauded the "brave" people of Arunchal and said that because of them, who were guarding the state as well as the country as sentinels, the northeastern remained an integral part of the country.
"The people here are real patriots as they salute their counterparts with 'Jai Hind' and are zealously protecting the state's territory... They gave a befitting reply to the advancing Chinese army during 1962 and the British and several army personnel from the state also fought with Pakistan during the Kargil war," he said.
Read: PM has failed Assam; Nido's death 'national shame', says Modi
While directly referring to the killing of Arunachal Pradesh youth Nido Taniam in Delhi, Modi cautioned the UPA government against underestimating the people of the state and added that it was the duty of the entire nation to protect the people and the state's territorial integrity.
Elaborating on BJP's mantra for development of the northeast, Modi pitched for the "three H" model of the growth for Arunachal Pradesh.
"Herbal, horticulture and handicrafts - these three Hs can give lot of opportunities to the people here," Modi said.
"Arunachal can be the world environment capital. It is no less than Switzerland," he said.
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Making a scathing attack on Congress governments, both at the Centre as well as in the state, for their failure in meeting the aspirations of the people, he said, "Neither dynasty nor casteism will benefit the country. Country will be benefited from development and 2014 elections will be fought on the development plank."
He also said that Congress government at the Centre does not listen to its own government in Arunacahal Pradesh.
"You need a government which is sensitive to the problems of every part of the country. The state does not have any opportunity in education or employment to offer the youth."
"There were special provisions in the budget for the development of northeast and Sikkim during A B Vajpayeeji's time," he said, adding "lotus will again bloom in the region."
Making an attempt to bond with the state, he said, "I come from Gujarat, a land that has very old and close relations with Arunachal Pradesh. The relation between Gujarat and Arunachal Pradesh brings the eastern and western part of our country together."
He also said that the "first rays of the sun bless this land. Arunachal Pradesh wakes up first and then the rest of India rises. The final rays of the sun set in Gujarat and tell us, we will rise again tomorrow in Arunachal Pradesh."
At Silchar, Modi flayed the Congress for catering to Bangladeshi infiltrators for political gain. "Two sets of people come from Bangladesh – one under a conspiracy to outnumber locals and the other that are forced to flee. The latter are Bengali Hindus, who the Congress targets by marking them as D-voters," he said.
Bengalis form almost 25% of Assam's voters. They form the bulk of 1.43lakh voters marked 'D', meaning 'doubtful'.
Vowing to scrap the list if the BJP comes to power, Modi also outlined the BJP's plans for tea plantation workers "exploited by Congress" for decades. Tea plantation workers – Adivasis from central India – have traditionally been a major Congress vote bank after Muslims.
Former Arunachal chief minister and Congress veteran Gegong Apang, who recently joined the BJP, also belongs to the Adi (hill man) tribe.
Going back to another favourite topic — mythology — Modi suggested the Modis inhabited the eastern and western ends of India because of Krishna and his wife Rukmini. “If we (Gujarat) have Dwarka, Krishna’s kingdom, you have the birthplace of Rukmini,” he said in Pasighat. Rukmini is fabled to have been born in Rukmininagar near Roing, headquarters of Lower Dibang Valley district.
At his last stop, Agartala in Left-ruled Tripura, he took on the “third front” driven by the Left parties. “The third front is like migratory birds that will vanish after the elections. We need a strong government at the Centre that can bring real development.”
Modi is looking for a foothold in the region whose party does not boast of any influence in the eight states.
The Christian-majority population in some hill states, the status of the Congress as the only "national party brand", more trust in regional parties and perception of the BJP as being "too Hindi belt" are the major factors behind its dismal presence in the region.
Modi's elevation as his party's prime ministerial nominee has coincided with a slide in the BJP's fortunes in the northeast, which offers 25 MPs.
The BJP's hope of expanding its base or even repeating its 2003 showing hinges on the kind of impact Modi will have on the region's electorate.
The visit prior to the Lok Sabha polls is also expected to test his acceptability as a leader beyond the Hindi heartland.
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(With PTI inputs and inputs from Itanagar and Agartala)