The message has been clear all along. Tony Blair has said that while he wants some important constitutional changes, he has no illusions about the "people's priorities". In other words, voters elected New Labour to make progress on schools and hospitals and jobs. Yes, there was - and is - limited demand for constitutional change, but the overwhelming priorities are clear.

Well, what's now happened is that the government's often impressive efforts to improve key services are under threat - thanks precisely to their less than impressive handling of the tricky issue of reforming the House of Lords.

The Queen's speech contained many radical proposals (notably in welfare policy) but its highlight was the bill to get rid of the hereditary peers. This policy was always going to be difficult, not least because the "hereditaries" are an awkward bunch when they put their minds to it. And they are certainly putting their minds to it now.

What's really put them out is the abrasive way the government has approached this issue, and it's almost guaranteed a parliamentary mess as big as any in recent memory.

Let's not be under any illusions. The hereditaries were never going to go quietly. They were never going to say: "thank you very much, it's been a great 900 years, adieu". But they have been given a fantastic weapon (or excuse) to make life difficult for Mr Blair.

In failing to come up with clear plans for a replacement second chamber, the government has placed itself in an impossible position. The only prospect as we speak is that the "bridging" chamber will consist of a vast number of "appointees" - those chosen by Mr Blair or those already in authority. It is not an advert for democracy in any shape, and will strike people as being no better (worse, in some ways) than the hereditaries themselves.

The government has already signalled that there will now be a long delay before the final shape of the Upper House is decided. This gives the hereditaries the perfect excuse to make untold trouble. Their much-rehearsed line is that they will not easily give up their status without knowing what's going to replace them in the long run.

This spells potential disaster for Mr Blair. What the hereditaries are threatening is wholesale disruption - affecting not just the progress of the bill that spells their downfall - but of every other big bill, too. As one prominent hereditary said to me: "What the **** have we got to lose, eh?". And he meant it. His view is shared by hundreds of others. And William Hague is playing a dangerous game by tacitly supporting their threats.