David Cameron thinks that if enough people sign an online petition, an issue should be debated by parliament. From the BBC:

Online petitions could be used to decide the subject of debates and votes in Parliament under a Tory government. Tory leader David Cameron said this would show the public “what their elected representatives actually think [...]

Whilst it’s common knowledge that a diet low in animal products is healthier, cheaper and better for you (and better for the animals, of course), it’s less known that it’s also a lot better in the fight against climate change.