Going along with my other thread on centre-right government, suppose the world leaders in 2020 include the following (I don't know enough about all of these country's politics to know if this specific list is possible, but just for clarity's sake):
USA: Hillary Clinton (Democratic)
United Kingdom: Jeremy Corbyn (Labour)
Canada: Justin Trudeau (Liberal)
Australia: Bill Shorten (Labour)
Mexico: Andrés Manuel López Obrador (PRD)
France: Francois Hollande (Socialist)
Austria: Werner Faymann (SPÖ)
Spain: Pedro Sánchez (PSOE)
Germany: Sigmar Gabriel (SPD)
Norway: Jonas Gahr Střre (Labour)
Italy: Matteo Renzi (Democratic)
Portugal: António Costa (PS)
Sweden: Stefan Löfven (Social Democratic)
Poland: Barbara Nowacka (United Left)
Netherlands: Diederik Samsom (PvdA)
India: Sonia Gandhi (INC)
South Africa: Jacob Zuma (ANC)
New Zealand: Andrew Little (Labour)
Hungary: József Tobias (MSZP)
Brazil: Dilma Rousseff (PT)
And, well... you get the idea. Furthermore, let's suppose that all of these parties have a strong enough standing in government to get solid legislation though (i.e. they're not part of any grand coalition, or only control one part of government). What might world policy look like? What would happen to the EU? Would the world economy start to look more socialist and regulated along side increasing supra-nationalist movements? How would issues like gay marriage and prostitution be treated? How would the East-West dynamic change, as well as the global north-global south dynamic?
He's not center left, he is a far left radical marxist
And your claim for knowledge on UK politics is?
Corbyn claiming to nationalize many industries, and wanting to institute a maximum wage is Marxist. And calling Isreal more evil then Palestine and America worse then Russia is not a center left position it is a far left position.
This is not a solely Marxist position. For example, Clement Atlee nationalized many industries, but he sided with the US in the Cold War.