Lyric discussion by bearhug 

I think this is lamenting how idle and weak people today have become. I don't think it's actually about the Spanish Civil War, but simply references it to get the point across, since many people who volunteered to fight back then gave up comfortable lives to do so.

'Bullets for your brain today But we'll forget it all again Monuments put from pen to paper Turns me into a gutless wonder'

This is saying how easily past wars become irrelevant. People in countries all over the world have fought against tyranny in many different forms, but once it's all over, we usually just put up a monument or two as a reminder of the sacrifices made and move on. It's little more than lip service, because few of us today would be willing to make the same sacrifices if it were inconvenient for us.

'Gravity keeps my head down Or is it maybe shame At being so young and being so vain'

This is saying how the majority of the younger generations today are far too superficial and materialistic. Maybe it's because we're so privileged now, but things like civil rights, freedom, justice, etc. are really not that high on our agendas anymore.

'Holes in your head today But I'm a pacifist I've walked La Ramblas But not with real intent'

I guess this is saying that even though you're being shot at and having to dodge bullets, the singer does nothing because he claims to be a pacifist. He's walked La Ramblas as a tourist rather than a fighter.

'And on the street tonight an old man plays With newspaper cuttings of his glory days'

Probably about how the older people who fought in past wars are now taken for granted.

'And if you tolerate this Then your children will be next And if you tolerate this Then your children will be next Will be next, will be next, will be next'

If we tolerate the bad things that happen around us, which we generally do, our children will be the ones that suffer.

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