Would they also be the kind of people who announce to the nation that they intend to plough on doing exactly what they've been doing before, despite missing pretty much every economic target they annonuced they were planning to achieve when they came into power? Because that's a pretty decent definition of 'mindless idealogue' to me.

Looking at the chart it is health care and medicare that are the problem. Social security are stable as a share of the economy. It is the rocketing health care that is the problem. If they dealt with that alone they could almost forget the other areas, including defence.

I didn't say either set of mindless ideologues was better than the other. I wish an equal plague on both houses.

Social security in America is a weirdly funded system, and it can't cope very well with rising costs and shrinking income. Viewed one way it could be seen as teetering on the edge of bankruptcy (in about 20 years), viewed another it is nowhere near that bad. However, either way, as a share of fed spending it looks likely to grow over the medium term (especially if they were to fix their healthcare and let poor people live a bit longer in the process). At the very least, some means testing so that the well off get less of the pie would be a really good idea.

Off topic, I know - but the Tories do seem hell bent on disassembling parts of the NHS, leaving the only option to use private care - much like the American system, to a lesser degree.
I'm not sure how you're not seeing that.
They may not come out and say "Right, we're scrapping the NHS and you can all invest in insurance schemes", for exactly the reason you say. Foolishness. However, they do appear to want to slowly but surely sow the seeds for that to happen, simply by cutting back on the NHS to the point where it's no longer fit for service, and you're left with the option of either using an underfunded, over worked system, or shelling out for private care which won't be to a better standard of expertise, it'll just cost you more up front.

That's an interpretation, but it's based on assumptions that I don't feel willing to concede. And bear in mind I am a Lib Dem who has never considered voting Tory in his life. But I don't think they're evil, or mad, or thieving, nor even any more corrupt than my own lot.

They have a belief that the NHS is a public good, that it should be maintained, that it was slightly malformed at birth, and that it needs serious reformation in order to stay in good shape into the future. To that extent I think they are right. And it bugs me that people are willing to deny it just because they vote the other way.

Either way, they think the basic blueprint for fixing the NHS involves private suppliers of many services, and public funding of the insurance. I am incidentally bored of pointing out that this is nothing like the American system, but very much like the French and German ones.

I'm happy for people to point out the flaws in this arrangement - the likelihood of creating bad markets that do nothing for the consumer; perverse incentives; counterproductive regulation and regulatory failings are all predictable problems. What I hate to see is simple minded demonology in place of clear sighted consideration. If we don't look for the good AND the bad, then we haven't really bothered looking at all.

Another serious problem with a bidding process is that private contractors are favoured at all costs over in-house teams via penalties for "overstating performance" outcomes achieved by public sector teams. So private contractors have as much as 20% advantage in any bids. All because they want to allow private bidders for ideological reasons not necessarily practical reasons.