Nov. 13: Queen Elizabeth's lunch for Prime Minister Narendra Modi is part of a new pattern in British diplomacy where protocol, once considered inviolate, is giving way to pragmatism of the American variety.

Precisely 10 months before the Queen hosted Modi at Buckingham Palace although he is not a head of state, British Prime Minister David Cameron had similarly received Pakistan's chief of army staff, General Raheel Sharif, at 10 Downing Street and held extensive talks with him though the general is not Cameron's peer in protocol.

According to diplomatic grapevine in South Asian capitals, the UK, which brokered a recent agreement between the intelligence agencies of Pakistan and Afghanistan, advised new Afghan President Ashraf Ghani to begin his Pakistan visit by meeting General Sharif. Protocol-wise this too had become a talking point.

As Modi departs on the second leg of his current foreign tour and lands in Antalya, Turkey, all eyes will be on Washington where important breaks with protocol can be expected during General Sharif's full five-day visit from Sunday.

Amid the glitz and glamour of Modi's diaspora engagement in Wembley, it is likely to be overlooked in the domestic public discourse that notwithstanding the consolidation of India-UK relations during Modi's visit, the Prime Minister's Pakistan policy continues to be a source of concern in Whitehall and in the White House.

Counter-terrorism, including a renewed threat from the radicalisation of Sikh youth in Britain, figured from the Indian side during Modi's talks in London. But an indication of British priorities on terrorism was evident from the absence from UK soil this week of Clovis Meath Baker, Cameron's counter-terrorism capability envoy.

Baker, who dropped his first and second names, William and John, in the shades of classical spies before accepting his current assignment, was in Islamabad as Modi arrived in London. Baker is an acclaimed expert on terrorism in South Asia who worked for his government out of Afghanistan both during the Russian occupation and soon after the ouster of the Taliban.

He also operated out of Pakistan, Turkey and Iran during critical times in those countries and was in Prague and Bratislava during the "velvet revolution" in Czechoslovakia.

The Queen honoured him with an OBE and a CMG for his intelligence work. Modi's top national security operatives, who were hoping to interact with Baker soon after their arrival in London, were disappointed to learn that his priority was Islamabad.

At the time of writing, efforts were under way to arrange a meeting that would critically increase the Modi government's understanding of the changing contours of Western engagement of Pakistan on counter-terrorism.

Britain and America have all along worked hand in hand on dousing the fires of the unfinished business of the Partition of the subcontinent 68 years ago.

When Gordon Brown made his farewell phone call to Obama in May 2010 just before stepping down as Britain's Prime Minister, he made a passionate plea that the US President try for a solution to Kashmir during the latter's visit to India in November that year.

Obama told Brown then that no one in India was doing more for a rapprochement with Pakistan than Manmohan Singh, then Prime Minister, according to sources in Washington who have seen the secret transcripts of that conversation.

Obama, Cameron - and Modi himself - are all aware that the comfort zone on India-Pakistan relations that existed in 2010 has evaporated after Modi's flip-flop on Pakistan in the last one-and-a-half years.

The British Prime Minister and the US President realise that pressure to resume talks will not work with Modi: they have concluded that the BJP's Prime Minister will be prickly about any frank discussion on Anglo-American interests in Pakistan and Afghanistan, according to sources privy to official thinking in London and Washington.

But Obama and Cameron are also hopeful that as a consummate politician who is responsive to messages that deliver the unstated, their actions in Islamabad will convince Modi that he cannot count on support in major Western capitals for the NDA government's policy of digging in its heels on engaging Pakistan.

Concern is high in both Whitehall and the White House that Pakistan's new strategy of developing and deploying tactical nuclear weapons that can hit India in the event of a war has transformed the fears of a nuclear conflagration in South Asia into the realm of realistic possibility.

Notwithstanding the substantially positive outcomes of Modi's stay in London, quite a bit of the Anglo-American diplomacy in the coming months will, therefore, hinge on the new conviction in Washington and London that the nuclear genie in South Asia urgently needs to be bottled.