No - India should not leave UN, that would be tantamount to pressure of backing off !! We should fight tooth and nail, and make our presence noticable by sending high profile high calibre representation to UN, rather than political appointees, who are weak and wilt under high profile diplomacy. Our Diplomats should be of sparkling personality, and able to mix and match at world arena. Our weekness is we are not able to lobby in the right places, and win influence from where it matters. Our wishes are high, but we are not able to turn this into reality. US have all the rooms bugged in UN, so before any Member Country would present their case, US is already prepared with the counter answers. Its also high time the UN is shifted from US, and probably position it in Europe or African continent - that would leave US become one amongst the rest of members, and take away their dominance.