Former government agent Liam Dunham is determined to kill his ex-wife Samantha Ryan by any means possible. He becomes like the very terrorists he was trained to fight. Samantha Ryan is a DoD Agency Director determined to protect her son from him, the estranged and monster of an ex husband while trying to prevent an international incident in the process.

Hi Presario2200,
Several issues I see with this logline:
1. Loglines don't mention character names
2. Why is the former agent determined to kill his ex, in other words, what does this accomplish? Is he taking revenge for something? The way you wrote it almost feels like he's doing this on a whim, becoming like a terrorist as you say. What makes him this way?
3. Why is she now protecting her son from him, if he wants to kill her? What is the international incident exactly? This sound all vague and muddled up to me...

Try to clarify who the hero is, what exactly he/she is trying to accomplish and what the tangible consequences of his/her failure will be.

You have no inciting incident. Why is your lead character determined to kill his ex wife? Why now? What happened?

No worries lewisricekrispy... :)

Just one last point on the irony front -- the reason why it's such a useful tool, and why it's considered such marketable element to a story etc, is that it clearly shows/ infers dramatic change in your protagonist... they are going to be FORCED to change if they are to succeed. There is no point for an antagonist to be in an ironic scenario, as the function of an antagonist is to do just that -- antagonize... not to change (antagonists can of course end up going through dramatic change, but including that in a logline serves no purpose, and wastes precious real estate...)