Even as some opposition parties are trying hard to bring every anti-BJP leader on a single platform to take on PM Narendra Modi, a common cause is apparently missing. This has become evident ahead of the oath-taking ceremony of new Karnataka CM HD Kumaraswamy. Top opposition leaders are attending Kumaraswamy's swearing-in\u00a0include UPA chairperson Sonia Gandhi, Congress national president Rahul Gandhi, West Bengal CM Mamata Banerjee, Delhi CM Arvind Kejriwal, Andhra Pradesh CM Chandrababu Naidu (who recently broke ties with BJP), former UP CMs Akhilesh Yadav and Mayawati. Most of these leaders attending Kumaraswamy's swearing-in are driven my many compulsions. Some of them are battling for survival on their home-turf. While the Congress has almost dragged itself to the level of a regional party for the sake of beating BJP, many others have lost their political might and some sense they will soon. HD Kumaraswamy swearing in LIVE Kejriwal is facing cut-throat rivalry from the ruling BJP at the Centre, Naidu is worried about losing Andhra Pradesh to YSRCP and BJP (if they form an alliance). Mayawati's BSP is presently reduced to the level of insignificance in Uttar Pradesh while Akhilesh Yadav's Samajwadi Party is also out of power. The only exception among these is Mamata Banerjee of West Bengal, who is apparently exploring her chances of leading a coalition in 2019 against Modi and keeping BJP grounded in her state. However, three leaders of significance have given the opposition show of strength opportunity a miss. Telangana CM K Chandrashekhar Rao, his Odisha counterpart Naveen Patnaik,\u00a0and Shiv Sena boss Uddhav Thackeray have decided against attending Kumaraswamy's swearing-in. Their absence on a joint opposition platform cannot be easily overlooked. Out of the three leaders, KCR and Patnaik are the most popular and powerful politicians in their respective states. In Maharashtra, Thackeray's Shiv Sena is a BJP partner and plotting its way to win a\u00a0majority of seats in next year's elections, where it will have Congress as one of the main rivals. In Karnataka, bitter rivals Congress and JD(S) have presented a formula for opposition unity that can be replicated elsewhere. But this is not something KCR wants. The Telangana CM has been advocating for a federal platform minus BJP and Congress. In Odisha, Patnaik has no visible and imminent threat from the BJP and by being seen in the company of Congress, he won't like to send a misleading message home. Rival parties may come together to take on a common enemy but political observers believe that fundamental differences in their outlook towards issues eventually break them apart. This has happened in past. The most recent example is of the Grand Alliance break-up in Bihar when JD(U)-RJD-Congress partnership failed to last more than two years.\u00a0In the present case, the differences are visible even before the start.