You hear the President criticized over the cost of the new Libyan military adventure. Whatever the merits or demerits of the President's new military activities, they are not really that costly. That's why they are so easy to do. The cost restraint for military adventurism is not really binding anymore. We could fight a number of wars all over the globe for a pittance of what it costs to support Medicare, Medicaid, Obamacare, and Social Security.
War is cheap! The volunteer army did that for us. It replaced conscripts with folks that really wanted to do this. So we have fewer of them, pay them better, and they do a better job. Plus, war technology has improved.
So, Obama gets a push-button war on the cheap. Whether it's a good idea or not is an entirely different story, but cost is not the issue.