Let’s rejoice in the fact that people who love each other will be able to marry. Because there’s a lot of joy in that.

At about 7pm tonight when MPs vote to introduce historic equal marriage legislation, David Cameron will rightly get a share of the credit. He has been brave enough to face down the majority his party over an issue of equality, but he hasn’t been able to take his party with him. He won’t be able to credibly claim this as a modernising moment for the Tory Party. Quite the opposite. Today will reveal the scale of the out to touch, backwards looking, deeply socially conservative (and in some cases downright bigoted) group that sits behind Cameron on the Tory benches.

Cameron could walk through the opposite lobby to as many as half of his MPs tonight. This may be a “free vote”, but as a rebellion it could be on the same scale as Iraq. Labour MPs broke the whip to oppose military action overseas. Tory MPs defy their leader to stop two people who love each other achieving equal rights and getting married to each other.

What a sad set of priorities.

The truth is that tonight’s legislation will pass thanks Labour votes (at least 225 by our latest count). Whilst it’s deplorable that 13 or more Labour MPs will vote against (and at least 5 will seek to avoid the backlash by abstaining), it’s clear that this legislation will pass thanks to Labour votes. Ed Miliband should have made that clear by whipping the vote, stating that equality is not a “conscience issue” and forcing those Shadow Ministers who are not expected to back the legislation to choose between voting with the rest of the PLP and their Shadow Ministerial roles. Alas Miliband took a different route – but it doesn’t mean that Labour should be denied the credit for this great leap forwards.

That a Tory leader should ever make a public stand on an issue of equality is testament to the enduring legacy Labour’s record. The great leaps forward for gay rights (and equal rights more broadly) over Labour’s 13 years in power is something that most Labour people are incredibly proud of, and which will never be reversed. After today Gay Marriage will be much the same. In recent weeks the fallacy has been repeated that Civil Partnerships were introduced with ne’er a word of discontent. Bollocks. They were opposed by the Tory back woodsmen then as Equal Marriage is opposed now. But, as former Tory MP Matthew Parris noted in the Times recently, Vote ‘no’ and you will blush to remember it.

By the time we all go to bed tonight, something truly historic will have happened in politics and our country, something which will bring newfound rights (and more importantly, joy) to millions. All those who wish to be married will now be able to do so under an equal system. The questions about how the legislation is flawed are for another day, as is the anger at those (on all sides of the house) who would have denied rights to people based on their sexuality.

Today, lets rejoice in the fact that people who love each other will be able to marry.

Because there’s a lot of joy in that.