Scottish National Party (SNP) not only causing Labour to lose seat in Scotland, obviously, but it probably also severely damaged Labour, its “progressive alliance”, in England.
Ever since Alex Salmon, the former SNP leader, declares “I’ll bring down the Tories and install Miliband” (see http://www.telegraph.co.uk/news/general-election-2015/11492933/Alex-Salmond-Ill-bring-down-the-Tories-and-install-Miliband.html); or “joked” about “I’m writing the Labour Party Budget” (http://www.bbc.co.uk/news/election-2015-32409909), Labour had been under constant attack from Conservative about the possible Labour-SNP “deal”. The following Conservative poster says a lot:
As a consequence, this causes some sort of “fears” in England. Labour leader Ed Miliband had since been busy trying to comfort the voters that he would not do any deal with SNP, be it formal coalition nor “confidence and supply”. This had been a major question people asked at the televised leaders’ debates, especially the BBC Question Time special on 30 April 2015. The impact was probably so bad that, Nicola Sturgeon, the SNP leader has to clarify that she “love England”, and “I hope nobody in England is afraid of the SNP – there is absolutely no need to be” (http://www.independent.co.uk/news/uk/politics/generalelection/nicola-sturgeon-says-there-isnt-an-antienglish-bone-in-her-body-10228042.html).
Ironically, the rise of SNP did not give what Scottish people want. I guess most Scottish people want a left-wing party but yet a Conservative majority emerged, which could be explained by Labour’s loss both in Scotland and England.
One has to wonder whether SNP indeed “secretly backs David Cameron” on purpose (http://www.telegraph.co.uk/news/politics/SNP/11514933/Nicola-Sturgeon-secretly-backs-David-Cameron.html).