I happened to attend the TMK concert in question. I am quite bemused by the fuss over it all. When I attend a carnatic concert or even visit a temple, I am very consciously paying homage to my wonderful civilisation and all the creativity that has risen from it. To me it was a nice way to finish the concert by singing the Anthem. Indeed I was moved to the point that my eyes went moist :$ . To me, there is nothing trivial about a Carnatic concert such that the N.A or a rendition of Vande Mataram is not worthy of it. I would actually love to experience this final tribute in every concert or dance programme I attend. (That the N.A may have been a tribute to George V is a different story

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I am inclined to believe that those critics who find fault with this have done so because they were not there to experience the feelings of patriotism behind it. I was a witness to the "regionalism" tainted speech and the rejoinder by TMK. I dont understand a word of kannada but even then, to me it was beginning to sound boring and repetitive as to induce a yawn in me. I think TMK was ticked off by the mistake of the presenter in firstly hijacking his own introduction of BS Purushottam, and then dwelling for way too long in singing the glories of Kannada culture - he should have been brief on this topic and reminder of regional achievements. Having photographed in detail, a few of the archaeological monuments of Karnataka's historical glory for my personal pleasure, I have all the respect for Kannadigas and their past. Just that the longish speech that showed no signs of ending - one that would certainly not go down in history as another great achievement for Kannada literary culture, and this may have ticked off TMK enough to interrupt it. The presenter was getting to be quite a bore honestly! I quite empathised with TMK getting impatient as it was not the end of the concert yet. I guess he decided to rub it in by singing the N.A towards the very end - he may have made the decision after the brief exchange of words.
Lastly, and off topic but I want to add - the brand of regionalism we see frequently today is only a reaction to the pressure of homogenisation that had risen in the last 60 years or so and stemming from a western mindset in the political class (Nehru's legacy) and the media. As is beautifully pointed out in a famous blog by SenthilRaja (which I wont reference here because it is seriously off-topic - google "pluralist encounter" if you want) - the western brand of homogenisation is actually an imposition of the language, culture, religion and customs of the dominant ethnic group on all others - the result of cultural, and often physical, extermination of diverse identities by one intolerant and powerful group. India is not like that - we all know that. For many thousand years, multiple ethnic groups, languages and sub-cultures have flourished without being overwhelmed by each other in traditional Indian society (some exceptions and events notwithstanding). Today that notion is being challenged by a hard reality that leaves the majority out of economic growth, prosperity and social empowerment, if they do not master a foreign language (English), and also by a level of centralisation in (inept) governance that Bharat has seldom witnessed in a thousand years. Hence I would keep a more tolerant view of regionalism, understanding that the root cause of this is actually a malignant form of thinking endemic to western civilisation and imported into our scenario with detrimental effect.
Regards