It is not the case that everyone is happy. War, climate change, the bizarre idea that it is normal for property to be unaffordable: the country is seething beneath it's British veneer. The left, however, is not benefiting in the way that we might expect. Why?
When you want to know the meaning of a word, what do you do? Look in the dictionary. The dictionary makers, the lexicographers, write their definitions based on common usage. They collect lots and lots and lots of examples, then select and categorise and describe. One reason why the left is not the automatic home of today's social anger is that "socialism" and "communism" have come to be firmly attached to a failed social system which largely ceased to exist at the end of the 1980s. The best of the left never considered these authoritarian societies as socialist, and this was of crucial importance to the survival of the most progressive of political currents, but to an ever greater majority that's of small consequence today.
Even "left" as a term has been impoverished by Labour's replacement of politics with performance. David Cameron has often succeeded in appearing more radical than the established "left wing" party in government, and what's more he has done so on some of the issues that are most important to the new generation of young people worried about the state of the world.
Should we pick a new word? Here's one suggestion:
The working class alternative could be called communism or socialism, but both are now identified with state ownership and top-down central command. It could be called real democracy or social democracy but the former is vague, while the latter has come to mean support for moderate reforms within capitalism. Economic democracy is preferable because that is what is meant. "Economic" from ancient Greece refers to the beneficial management of resources and labour in households, estates or cities. Democracy, the opposite of oligarchy — rule by the rich — is supposed to mean rule by the people. (Economic Democracy, Allan Engler, 2010, p. 46)