Looking like the kind of bad morning a Government can have when it hasn't been honest for over two years about what can realistically be achieved in a major negotiation...
First, other countries / the EU have interests. This will apply to trade deals, and certainly applies to the EU. If they are the EU or US they expect a smaller country like the UK to give them what they want. In the case of the EU fishing is an issue... telegraph.co.uk/politics/2018/…
Second, domestic interests will threaten your majority if you haven't got opposition support. Yes, we're back to Ireland, and the fact that there will always have to be a backstop, whether or not it is intended to be used... thetimes.co.uk/edition/news/n…
Finally you'll always have rebels in your own party in a major negotiation, and failing to acknowledge this and pretending you can keep the party unified just delays the time until that unpleasant truth must be faced... theguardian.com/politics/2018/…
Worryingly it looks like the Government will once again cave under this pressure (earlier in the week I thought it might not) if this line from The Times story is well sourced. But we're running out of road, very quickly... 
It isn't though as if there is any alternative. Those Conservative MPs wanting to 'go back to Lancaster House' are ironically cherry picking from that speech - as I discussed last night -
No-deal remains as disastrous and unpalatable to Parliament as ever. The outlines of a deal have been there for some weeks, so we are back to the need for the Government to bring this back to Parliament, and then let it be debated properly /ends
PS @tconnellyRTE has a typically insightful thread onto the PM's letter to the DUP, it does sound like the letter is stretching several points beyond credibility
