It was Labour who started off the severe cuts in wages and welfare benefits under James Callaghan in the 1970s. Callaghan pioneered the monetarist policies then taken up by Thatcher.
Many argue that a Corbyn-led Labour government would somehow galvanise social movements. However let’s look at the example of Bennism in the early 1980s. Bennism was a similar movement to Corbynism. It mobilised around the left Labour figure of Tony Benn. In fact both Corbyn and McDonnell were minor figures within Bennism, as were some of their present associates. There was great hope that Benn would become deputy leader of the Labour Party until he was defeated by Denis Healey in 1983. In the process a large number of activists from the various social movements, women’s groups, gay liberation groups etc. who up till then were existing outside the Labour Party, were now dragged into Labour and in the process demobilised these social movements. A similar phenomenon happened alongside this when Ken Livingstone ran the Greater London Council from 1981 to 1986 and developed his “rainbow coalition”, involving the same social movements mentioned above, absorbing them into the GLC. Again the result was demobilisation, with people looking towards the GLC administration rather than relying on their own action. Livingstone backed down against Thatcher on tube fares and setting local rates and there was no significant response on the streets.
Going back to Syriza, we saw a situation where it persuaded people to rely on its being in power and fighting against the austerity measures imposed by the EU, the IMF and the World Bank. Of course Syriza broke everyone of their electoral promises. The Syriza member Stathis Kouvelakis had later to admit that the negotiation process with the EU “by itself triggered passivity and anxiety among the people and the most combative sectors of society, leading them to exhaustion”. The Greek social movements have taken a long time to recover from the Syriza experience and that could be the same scenario with a Corbyn government. Again we repeat, we have to rely on our activities and our own organisation of grassroots struggles.