28/04/2015 12:13 BST | Updated 28/06/2015 06:59 BST

The Real Reason Labour Won't Do a Deal With the SNP

The famed American statistician Nate Silver has suggested there could be an "incredibly messy outcome" to the election.

Silver, who correctly predicted the result in every state in the 2012 US election, took star billing for the BBC this week as he, and the always affable Richard Bacon, explained why it was so hard to predict what will happen on 7 May.

We were introduced to tactical voting and were told two-party politics was at an end. Next week Richard explains how eating food is important to keeping us alive.

It wasn't the usual hard-hitting Panorama we have come to expect - at times it felt like we were watching Newsround - but it was illustrative in one respect - nobody appeared to have told Nate that forming a coalition with the SNP is off the table. More than once he talked about Labour joining forces with the Scottish nationalists although his best guess, in terms of the overall result, suggested together they still wouldn't have enough MPs to form a majority government.

Ed Miliband has made it clear, on numerous occasions, he won't get into bed with Nicola Sturgeon. In fact some of his most passionate responses have come when dealing with this question. We now know Russell Brand has more chance of securing a cabinet position as there is clearly a very good chance he and Ed have at least shared a bed.

We are repeatedly told by the Conservatives and Labour that they would not enter into a formal agreement with a party that wanted to break up the union.

However this is where our disingenuous political establishment once again rears it ugly head and distracts us from what's really going on.

In theory Labour and the SNP are natural bedfellows. They are both left leaning however the reason Miliband is being so definite about saying no has nothing to do with Scottish independence and everything to do with an issue which has much more far reaching implications.

The SNP leader has been clear from day one that scrapping Trident is a 'red line' and is on record as saying that the 'non renewal' of the UK's nuclear deterrent is an "absolute priority". In fact it the Scottish Nationalists' only red line.

Despite the fact that most Labour supporters and Labour candidates would also like to see Trident scrapped, Ed has stuck to his guns. Labour would never, ever, ever, ever give it up. Ever.

If that seems a little strange the reasoning becomes more clear when you consider what abandoning a nuclear weapons strategy actually means and why, if it was ever seriously considered, would illicit an extraordinary reaction from across the Atlantic.

We need to keep Trident to keep our place as a permanent member of the United Nations Security Council alongside China, Russia, France and the US. The Americans need us to keep the Russians and Chinese in check. Can you imagine the response if we were forced off and the Chinese and Russians wanted the replacement to come from Asia? Pakistan perhaps? Or what about the Ukraine maybe?

Every British government knows that its number one priority is to main the 'it's-special-when-it-suits-the-Americans' relationship. As red lines go it's up there with ensuring we have oxygen to breathe.

Even if Miliband looked a lit bit indecisive in answering the question, alarms would start going off in the Pentagon.

The Labour leader knows that a non-SNP path to power is the only card he has to play, no matter how messy the alternative options might be... including another election in October.