Is Narendra Modi facing a mutiny?

Mr Modi and Mr Shah are the most powerful leaders of BJP

US founding father Thomas Jefferson once said a "little rebellion now and then is a good thing, and as necessary in the political world, as storms in the physical".

After suffering two consecutive - and humiliating - defeats in the Delhi and Bihar elections, India's ruling BJP, many believe, also needed a small rebellion to shake it out of its complacency.

On Tuesday evening, four senior party leaders, led by India's former deputy prime minister LK Advani, fired what was clearly a broadside against Prime Minister Narendra Modi and BJP chief Amit Shah.

"The principal reason for the latest defeat is the way the party has been emasculated in the last year," said the leaders in a statement, criticising the party's campaign strategy after Sunday's humiliating defeat in Bihar. "A thorough review must be done of the reasons for the defeat as well as the way the party is being forced to kow-tow... and how its consensual character has been destroyed."

The scathing missive was strategically timed: it came hours after the government eased regulations for foreign direct investment in at least 15 sectors to boost reforms and inject some feel-good before a gloomy Diwali, the Hindu festival of lights.

The challenge also came ahead of Mr Modi's much-hyped three-day visit to Britain. It was clearly intended to embarrass the prime minister.

Controversial politician

Nilanjan Mukhopadhyay, who has written a biography of Mr Modi, says revolt by the party elders - "oldies come out of cocoon", headlined The Economic Times - is mainly aimed at scuttling BJP president and Mr Modi's closest aide, Amit Shah's chances of beginning a fresh term as party president in January.

Mr Shah, a ruthless tactician, is often described as Mr Modi's Karl Rove and the man behind the party's sweeping win in last year's general election. At 50, he is also one of the youngest presidents of the Hindu nationalist party.

He is also a controversial politician, who is accused of sanctioning the killing of a Muslim civilian in 2005, when he was the home minister of Gujarat state. He spent more than three months in jail after which he was released on bail. Mr Shah denies the charges.

Critics say Mr Modi and Mr Shah, both from Gujarat, have completely taken over the BJP, and are running what used to be a loose, collective and largely democratic party as their private fief.

Successive defeats in Delhi and Bihar have taken the sheen off Mr Modi and Mr Shah

The duo have also successfully managed to sideline the old guard.

Mr Advani, one of BJP's architects, was removed from the party's parliamentary board last year, and kicked upstairs to a newly formed Margdarshak Mandal (guidance committee) an ineffectual body of elders, along with other veterans like former minister, Murli Manohar Joshi, and former prime minister Atal Behari Vajpayee.

Mr Joshi, still remembered for his incendiary rhetoric in the run up to the 1992 demolition of the Babri mosque by Hindu hardliners, was forced to vacate his parliamentary constituency, Varanasi, to make way for Mr Modi last year.

'Yesterday's people'

Clearly, Tuesday's revolt was initiated by some of the party's most experienced leaders, but they are in their autumn of their lives, marginalised and ignored by the party - supporters of Mr Modi uncharitably call them yesterday's people.

They have been seething against what they think is the takeover of the party and government by two upstart outsiders from Gujarat. They are upset with what they - and many in the BJP and government - believe is their centralised, take-no-prisoners style of working. "But they do have moral authority and they have been ignored. They have nothing to lose, and they have spoken," says analyst Shekhar Gupta.

This rebellion doesn't really mean that the old guard has been resurrected. "The moral authority of the four elders is being overestimated," says commentator Ashok Malik. Beyond embarrassing Mr Modi and Mr Shah, it is not clear whether they will be able to force a change in the leadership of the BJP, unless they are joined by the party's younger and more significant leaders. Mr Modi will be loathe to let go of Mr Shah, who remains his most trusted aide.

Also, despite the recent setbacks, Mr Modi remains the BJP's most powerful leader, and would possibly win - albeit by a diminished margin - if a general election was held today.

But most believe that this missive may spur the leadership and the party to undergo a course correction: less bombast and hubris while campaigning for votes, listening to and promoting more local leaders, and returning to good old fashioned realpolitik of political give and take.

After all, a small rebellion can be a blessing in disguise.