Clouds, the optimist believes, have a silver lining. A senior Congress leader had alluded to the idiom while describing the likely consequences of Rahul Gandhi’s disqualification from the Lok Sabha after being convicted in a case of defamation. The proverbial silver lining spotted by the Congress politician concerned the coming together of a disparate Opposition to take the political battle to the ruling Bharatiya Janata Party, which has been the principal beneficiary of the disunity. The Congress cannot be blamed for its nascent optimism. The Communist Party of India (Marxist) has been vocal in its criticism of Mr Gandhi’s disqualification. Arvind Kejriwal has lent his voice of support. At long last, the Trinamul Congress decided to join the protest march by members of the Opposition on Monday. The developments may be heartening for the Congress. There is, after all, no love lost between the Congress and many of these outfits because of their long history of regional rivalry.

A united Opposition could pose a formidable challenge to the BJP. Is there then a reason for the BJP to feel uneasy? The answer, unfortunately for India’s Opposition, is not in the affirmative. The elephant in the room when it comes to Opposition unity is the political rivalry in states that taints most of the parties that constitute the national Opposition. The TMC, smarting from its defeat in a recent by-election in Bengal where the Left and the Congress were allies, is unlikely to dine with the Congress in Delhi. The CPI(M), which has spoken up in Mr Gandhi’s defence, is a bitter rival of the Congress in Kerala. Mr Kejriwal’s party and the Congress fight tooth and nail in Punjab and Delhi. There are ideological roadblocks too. Uddhav Thackeray, desperate to recover lost ground in Maharashtra, has already objected to Mr Gandhi’s recent remarks on V.D. Savarkar. Mr Thackeray’s Shiv Sena, in its undivided form, was the Congress’s ally in Maharashtra. This combination of political competition and ideological differences nullifies the possibility of a broader, durable alliance among the BJP’s opponents. Mr Gandhi’s ouster from Parliament is unlikely to serve as a glue. The tragedy is that in over eight years since the BJP’s enthronement, the Opposition has not been able to find a way around these chasms to take on the BJP. Perhaps it is only the Congress that has spotted that illusory crack in the cloud.