India -- one of the main supporters of the anti-Taliban Northern Alliance, which had managed to hold on to a tiny sliver of the country in the north during the five years of Taliban rule -- and Pakistan are among them, in addition to Iran, Russia and, of course, the United States.
Afghanistan has a long and tumultuous history full of warring tribes and ethnic factions, including a decade of brutal Soviet occupation from 1979 to 1989.
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Its main advantage -- its geography -- has perhaps also been its main drawback. Anyone who controls Afghanistan controls the land routes between the Indian subcontinent, Iran, and resource rich Central Asia. Almost every major power therefore wanted a slice of the pie.
Today, flanked by Iran on the west, Pakistan on the east and the Central Asian republics of Turkmenistan, Uzbekistan, and Tajikistan in the north (and a very small stretch of border with China in the northeast), the country's geo-strategic importance has multiplied manifold.
What are India's interests in Afghanistan today?
Economically, it is a gateway to the oil and mineral rich Central Asian republics. Also, the massive reconstruction plans for the country offer a lot of opportunities for Indian companies.
Historically, apart from the five years of Taliban rule from 1996 to 2001, India has enjoyed good to excellent cultural and economic relations with Afghanistan. Indian movies are reportedly a staple part of the Afghan culture, while Afghan shawls and dry fruits, among other things, come into India both legally and illegally.
Strategically, an actively pro-Delhi regime in Kabul (at the moment, fierce warlords rule most other parts of the country) would rattle Islamabad, which has traditionally seen Afghanistan as its backyard.
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Why is Pakistan averse to giving India transit rights through to Afghanistan?
Officially, the reason is Kashmir.
The issue of transit rights has affected the talks for the gas pipeline from Iran, with India's request for a highway parallel to the proposed gas pipeline from Iran being repeatedly rejected by Islamabad.
Pakistan has linked almost all economic issues, including granting of MFN status to India, to the resolution of the Kashmir dispute.
Unofficially, it has to do with Pakistani fears that it would be swamped with Indian imports, and its desire to retain hegemony over trade with Afghanistan. A huge chunk of Afghanistan's trade is channeled through Pakistani ports like Gwadar and Karachi.
'We have to induce Pakistan to fall in line'
What are the other differences with Pakistan?
Pakistan is wary of the number of Indian consulates in Afghanistan -- in Jalalabad, Kandahar, Herat and Mazar-e-Sharif. It believes that these missions are being used to foment unrest across the border in Pakistan's Balochistan and other frontier provinces. Some Pakistani officials have accused the Indian missions of printing and circulating fake Pakistani currency and recruiting Afghans to carry out sabotage in Pakistan.
India, however, asserts that 'It's for the Afghans to decide which countries get to set up consulates in their countries.'
'We have strong bilateral relations with Afghanistan, and we want to help them rebuild their country. India also sees Afghanistan as a route to Central Asia. So it has nothing to do with Pakistan,' a government spokesman said.
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But a Pakistani official was quoted as saying that 'Pakistan wants a stable Afghanistan, because they are next to us, and any instability up there will leak into Pakistan.' As 'for the Indians, we have told Afghanistan that if they open those consulates in southern Afghanistan, the only purpose is cross border terrorism into Pakistan.'
What is the significance of Prime Minister Manmohan Singh's visit to Kabul?
Since the fall of the Taliban, India has been one of the primary donors towards Afghanistan's reconstruction. Apart from presenting aircraft to kickstart its Ariana airlines, India has been active in building roads, schools, hospitals, power and communication networks, besides training its military, police, bureaucrats, diplomats and even businessmen.
The prime minister's visit is aimed at consolidating these efforts, to send out a message of solidarity and trust with the war-scarred nation, still deeply divided along ethnic lines.
According to Foreign Secretary Shyam Saran, 'On the political side, really our effort has been to contribute to the strengthening of this national consensus, inter-ethnic harmony in Afghanistan because we believe that for the return of political stability it is important for the different ethnic communities to work together.
'We have supported President Karzai in this direction the past and we will continue to do so,' he said.
Earlier on rediff:
Expert Dr Barnett Rubin explains Afghanistan on the rediff Chat
'The state with the closest ties and strongest links to Afghanistan is Pakistan'
'Afghanistan will remain ripe for the picking'
An exclusive interview with Mullah Omar
'We like fighting:' What Najibullah told A K Hangal and Mukul Anand
Afghan elections: Who's Who
'There's no justification for the US war in Afghanistan'
Did Osama miscalculate?
Karzai rekindles affair with Shimla
Iran's hand in the Afghan mess
Parliament will be the heart of democracy in Afghanistan: PM
Pakistan to closely watch PM's Afghanistan visit
First Look: Manmohan Singh in Afghanistan
India, Afghanistan sign 3 accords
Text of Indo-Afghan Joint Statement