Labour and the Lib Dems are “rational”?
Not for a long time now: Labour sold their souls to the devil once Blair took over, while the Lib Dems should never be forgiven for supporting the Tories in the 2010 coalition (and getting f*** all in return, lest it be forgotten).
Anyone whose brain has not been eroded by nearly 50 years of neoliberal propaganda has only one option: vote Green.