What could anti-austerity look like?

So austerity isnt working and is being roundly rejected by European voters. What could the alternative look like?

A debate I seem to be constantly having with people recently is that there is no central rallying cry for the 21st Century. Other centuries have had ( rightly or wrongly) radicalism, republicanism, imperialism, communism, fascism, socialism and so on, but what is OUR 'ism'?

It strikes me that, to reject austerity, we need an alternative. We've also recently seen companies like Amazon making £7bn a year in the UK and paying zero tax, we know about tax havens and tax avoidance and how much the exchequer loses as a result. Can we overturn such things? What are the consequences?

If we tell Amazon, Vodafone, Arcadia et al to pay up- what happens?

Likely a WTO ruling against us, but can that be enforced? If we say 'No, we arent paying those fines', what can they do?

Does this approach mean we become Isolationist? If so, several questions come up? Can we feed ourselves? Can we freeze foreign owned assets here to keep ourselves going? Could we defend ourselves if necessary? The last question might sound silly, but we only have to look at Cuba, Guatemala in 1954, even Iraq, to see what happens when countries nationalise or restrict economic access.

If not, what else can we do to change things, to get out of this global boom and bust; away from unfettered and unfair capitalism

I know its a simplistic argument, but I really dont know enough about how the world either operates now, or could operate in a diufferent way, and I';d like to. What about energy security? Is globalisation just too ingrained? I just think that the current economic model needs overturning and it wont just happen by itself

So... loads of questions- I'd just like to start a discussion really.