Wembley stadium was freezing on Friday. I speak with authority. I was there in the press seats for five hours - at the 'UK Welcomes Modi' rally, along with 50,000 or more exuberant, impatient UK-based supporters of India's prime minister. It really had the air of a festival. Lots of Indian flags on display ... traders who usually sell to football supporters we're doing well with 'We Love Modi' scarves in India's colours at £10 a time ... and the 'mass' demos outside ended up as just 300 or so aggrieved Sikhs and Kashmiris.
David Cameron introduced Modi - a clever move. The tens of thousands in attendance vote in the UK not India - and most are natural Conservative supporters. Cameron began his brief speech with palms folded, saying: 'Namaste Wembley' - and he ended with a clever adaptation of the BJP's 2014 election slogan, 'Acchhe din zaroor aayega' (good days will certainly come). He stayed to listen to Modi's speech - sitting alongside his wife Samantha, wearing a red sari and looking comfortable in it.
And Narendra Modi's address to the rally? A master class in playing to the Wembley crowd: confident, witty, accomplished. There wasn't a huge amount of substance in it - beyond his key message: 'We don't want the charity of others - what we want is equality. India stands firmly on the same footing as everyone else.'
He spoke mostly in Hindi, but played up the Gujarati angle - announcing the start of direct flights between Delhi and the main city in Gujarat, Ahmedabad. As you might imagine, that went down well with a crowd which was probably preponderantly Gujurati.
At times, the Indian PM paused in his speech - chants of 'Modi. Modi' filled the silence. He clearly relished the adulation - after the election setback in Bihar, and with all the (well merited) concern about majoritaranism, basking in the warmth of the Wembley crowd must have been quite a tonic.
After the hour-long speech, Modi did a cup winners' style lap of the Wembley pitch, acknowledging the crowd and lapping up their love.
Wembley was clearly the highlight of Modi's three days in London - though the British government provided much more pomp (lunch with the Queen ... Red Arrows flypast ... Scots Guards guard of honour ... a night at Chequers) than is customary for a mere head of government.
The first time I visited New York was three days after 9/11 - there was still a huge plume of dust and smoke rising from Ground Zero.
Last week I visited Ground Zero again, just days after bin Laden's death. It's not given closure to the pain of that attack, but it felt to me that the killing of bin Laden had helped to draw a line.
I was struck by how little triumphalism was on display in the city. There were some 'Obama got Osama' T-shirts for sale, but you had to look hard to find them. And I had to scour even further to find these 'Mission Accomplished: 05 01 11' badges, themselves a fairly restrained commentary on the operation against the ObL compound in Abbottabad.
The only, and I do mean only, celebratory placard on display near Ground Zero was in the name of - wait for it - the Mumbai branch of the BJP.
Mumbai has also of course suffered immensely at the hands of jihadi attackers. And the wording of the sign is hardly inflammatory. Still, to me it struck an awkward note.
Andrew Whitehead's blog
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