I'm not going to take on the common "she's just trying to scare people into voting for her" argument. Instead I thought I'd write a short editorial on how this ad works with the undecided voters in the upcoming primary states.
On the one hand, you could argue that her "it's 3AM in the White House" ad was successful (even though it's been mocked ever since), so why not create a similar ad for this primary?
The problem is, if her target demographic is undecideds who plan to vote, chances are they are paying attention and might think that she is changing her tune from "I can do anything" to "you will be safer with me than with Barack" because she is desperate. Somehow, I don't think the common undecided voter this late in the game is going to vote for someone who is willing to do just about anything to stay in the race. Maybe if she had touted her experience in dealing with international problems earlier in the game, made Obama look young, naive and inexperienced earlier, he wouldn't have gotten the momentum that helped him to win in so many states.
Then again, maybe their internal polling suggests that focusing on security will help her reach undecideds, because when in doubt, they go with the person who will most likely protect you and your children from foreign terrorists. They forget about issues of the economy, religion, education, healthcare, and the environment. It sounds silly, but it is a post 9/11 world. I think it's fair to say that the next president will have to deal with more specific foreign threats that anyone pre-President G.W. Bush (yes I realize we fought 2 World Wars, but those were declared, not initiated by a single person with a suitcase bomb in a busy street). Regardless of whether it's true that Hillary will be better at security than Barack, ads like the one released today certainly plant some doubt in the minds of her target audience.
It certainly is an interesting study in political advertising. The people who discuss this ad the most have already made up their mind. I'd love to talk to people on the margin, the types of people that Hillary's campaign was targeting, to see how this advertisment affect their voting decision.