Ed Miliband today made it clear he will not support "waves of irresponsible strikes" as he sought to damp down claims that he would reward unions that helped him to secure the Labour leadership.
He told Labour's annual conference the party had to win public support and avoid alienating people and adding to the book of "historic union failures".
With senior union leaders sitting in the conference hall to hear his first keynote speech as leader, Mr Miliband said: "That is why I have no truck, and you should have no truck, with overblown rhetoric about waves of irresponsible strikes.
"The public won't support them. I won't support them and you shouldn't support them either."
Bob Crow, general secretary of the Rail Maritime and Transport union, said: "Any Labour leader who fails to support those workers in the frontline of defending jobs and services against the ConDem assault will get slaughtered at the polls.
"Ed Miliband has to decide whose side he is on - the working class on the streets and on the picket lines or the ConDems and their corporate supporters.
"All the signs are that he is already caving in to pressure from the right-wing press and as a consequence he will alienate millions of voters who are right at the sharp end of the cuts programme."
Mr Miliband said it was vital that workers had a voice to speak for them, telling delegates that during the leadership campaign he met a group of dinner ladies who had to buy their own uniforms and had their shift patterns changed at a moment's notice.
"Frankly conference they were being exploited. So they looked to their union to help them. They weren't interested in going on strike - they loved the kids they served and they wanted to serve their schools.
"But they wanted someone to help them get basic standards of decency and fairness.
"Responsible trade unions are part of a civilised society. Every democratic country recognises that. But all of us in this movement bear a heavy responsibility.
"We want to win an argument about the danger this coalition poses to our economy and our society."
The Labour leader said this "new generation" demanded responsibility from business as well as unions, adding that he had recently met a care worker in Durham doing "one of the most important jobs in our society".
"If it was my mum or dad, I would want anyone who cared for them to be paid a decent wage.
"But she was barely paid the minimum wage, and barely a few pence extra for higher skills. She told me that she thought a fair wage would be £7 an hour because after all she would get that for stacking shelves at the local supermarket.
"I believe in responsibility in every part of our society. That's why I believe in not just a minimum wage but the foundation of our economy in the future must be a living wage."
Mr Miliband said the tax system should reward responsibility, as he called for a living wage, high quality apprenticeships and family-friendly employment.
The new Labour leader has been dubbed Red Ed by sections of the media after support from union members helped secure his dramatic victory over his brother on Saturday.
Mr Miliband said responsibility applied to company chief executives and to people who were able to work.
"This is one of the hardest issues for our party because all of us know in our communities people who are in genuine need and who worry about the impact of new medical tests or changes to rules on them."
The Labour leader said some people had also become trapped in the benefits system, which was not in their interests.
"We are right when we say it must be challenged. Reforming our benefits system is not about stereotyping everybody out of work, it's about transforming their lives. Real help matched with real responsibility."
Mr Miliband said he will look closely at the Government's welfare plans, adding that there should be no arbitrary cuts to benefits.
Delegates applauded Mr Miliband when he spoke against strikes, and there were shouts of delight when he pressed for a living wage.
He was also loudly applauded when he said the gap between rich and poor mattered, continuing: "It doesn't just harm the poor, it harms us all. What does it say about the values of our society, what have we become, that a banker can earn in a day what the care worker can earn in a year?"
Unions have been campaigning for increases in the national minimum wage, arguing that workers needed a living wage to survive.
Mr Miliband said the new generation must find a new way of conducting politics, turning to some of the names he had been called.
"Wallace out of Wallace and Gromit - I can see the resemblance. Forrest Gump - not so much. And what about Red Ed? Come off it. Let's start to have a grown up debate in this country about who we are, what we believe and what kind of country we want to build."
Mr Miliband, developing one of the main themes of his leadership campaign, called for families to be "protected" and spoke out against long working hours.
"Families can't do the best job if they are stressed out, working 60 or 70 hours a week, can't be there when the kids get home from school, doing two or three jobs.
"We've got to change our culture on working time, not just for the good of families, but because it is through family that we learn right from wrong, develop ambitions for ourselves and show kindness and respect for others that is the foundation of our society."
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