Demanding one isn't the way to get it.
Look, you can't have a debate with people who don't want to debate you.
There are two groups of people you can debate on the abortion debate.
1) Hardcore pro-aborts.
2) Everyone else.
The hardcore pro-aborts won't debate.
Everyone else doesn't care.
And what do I mean when I say people "don't care"?
There's a concept called saliency. Yes, most people would support a late-term abortion ban in Canada.
But support for a late-term abortion ban is a mile wide and an inch deep.
There's no saliency.
If you want an abortion, I suggest that you do it by assertion.
Just keep stating truths, and then people will be irked enough to consider it and/or debate it.
When you get enough people to care about what you're saying, that's when you will have a debate.
If there's no debate it's because not enough people care enough to debate you.
This is the reality. That's why Stephen Harper is not having an abortion debate.