Help choose my next book's cover

I am writing a textbook on homeland security, due out next year and my publisher has a poll to help choose the book's cover.  Check out the sample covers and vote on ones you like best - be sure to leave feedback as well - my publisher, cover designer and I will be reviewing your feedback in helping make a decision.  Here's more from my publisher:

Homeland security expert Ehsan Zaffar will be releasing a textbook on homeland security policy tentatively entitled Understanding Homeland Security: Foundations of Security Policy. This is an opportunity for you to weigh in on the look and feel of your textbook and provide critical feedback to Elsevier and the author. We look forward to your insights.

Check out the website for more information about the author. His unparalleled access to insiders in the homeland security community has produced revealing interviews with many of the leading players. His textbook discusses hot topics from border security, cybercrime, and terrorist financing to homeland security law and policy.

Follow Mr. Zaffar on Twitter @ezaffar.