Decide on the emotional issue you want the reader to confront. The issue should be one that evokes strong reactions so your novel can be approached in an aggressive fashion. This could be, for example, the issue of rape or child abuse.
Choose characters in the story that present different sides of the emotional issue. It can be difficult to conceive of a character who believes in something you may find abhorrent, but remember that there are some places in which the honor killing of a sibling is considered justified, for example.
Decide what your characters want and need. The storyline of the novel comes as your characters go about trying to get what they want and meeting obstacles in their quest to get it.
Plot your novel in outline form in order to get ready to write. Remember that your characters have to confront each other and try to convince each other of their convictions. Make the reader sympathize, at least partially, with each character, which will help the reader's emotions to be exposed uncomfortably. When the reader is torn between characters on the opposite sides of an emotional issue, the reader is exposed, which is partially the goal of an aggressive novel.
Add subplots that show the nuanced facets of the emotional issue. These subplots may involve secondary characters who have their own needs and desires that are related to the core conflict. These subplots can help to nudge readers into understanding both sides of the emotional issue.
Write the novel, organizing chapters so that they have taut chapter endings that are emotionally charged, confronting the reader with his own emotions.
Ask impartial readers to give you feedback when you're done writing. Ask about sharpening the emotional issues presented in the book and rework accordingly.