John McCain is 72 years old, and despite showcasing his 95 year old mother and his own protestations to the contrary, 72 is, well, 72. Couple that with the aging process that inevitably occurs under the stress of 5+ years of deprivation and torture in prison, and there is enough reason why anyone professing to put "country first" would have an MRI (magnetic resonance imaging) of the brain to assuage that country's concerns.
McCain has also displayed many signs of inattention. The 'expert' on national security and Iraq could not get straight the relationships among the Sunnis, Shia, al-Qaeda and pro-Iranian militias on several occasions close in time. He makes statements absurd on their face such as "Sarah Palin knows more about energy than anyone in the United States". The Chairman of the Commerce Committee did not know that the SEC is an independent entity, not subject to being fired by the President. He rolls from one inconsistency to another, and he has no anchor. Just today, he petulantly rejected conversations with the Spanish Prime Minister, one of our NATO allies. He chose Sarah Palin with one telephone conversation with him.
Of course, McCain could just have attention deficit disorder (ADD) to explain his inattention, lack of focus on detail, persistent gaffes and impulsiveness. And, he may just be a pathological liar. But, an MRI would reveal the degree of brain atrophy and whether there are early signs of other degenerative disease such as Alzheimer's. A negative MRI would assuage such concerns.
McCain has also had melanoma. While melanoma has been portrayed in the press as a "skin cancer", that characterization is misleading. Unlike typical skin cancer, melanoma can spread widely in the body to almost any organ, including brain, lung, bone and liver. It is very true that brain imaging only occasionally detects metastatic melanoma in patients without symptoms ("asymptomatic"). Thus, it is not an efficient screening mechanism for all patients with melanoma. Moreover, the only treatment is palliative, and the median survival in patients with melanoma spread to the brain is measured in months, not years.
Nonetheless, McCain wants to be President of the United States. If he is serious about putting country first, he will have an MRI to provide assurance that, for now at least, he has no brain metastases. The detection rate in asymptomatic patients is low, but not zero.
And, finally, Sarah Palin. She seems genuinely convinced that she is ready to be President of the United States and that is what is truly scary. The less one knows about what another job really is, the easier it seems. We just went through 8 years with another "President" who had shown no evidence in his entire life of actually thinking through complex matters (and that, really, is the key deficit).
She is, as Bush was, shielded from questions so that his lack of thought would not be revealed. She declared her knowledge of foreign policy based upon being able to see Russia from her State, and Bush determined that we could work with Vladimir Putin by looking into his eyes and glimpsing his soul. Before invading Iraq, Bush did not consult his own father, the only man in the country with direct experience making a similar decision against the same foe--instead he looked to a "higher father". Sarah Palin believes that our Army is in Iraq on "God's mission".
Palin, like Bush, brims with confidence of her ability to do the job. Indeed, it is only because George Bush has so demeaned the Presidency that Sarah Palin is not rejected out-of-hand. Chuck Hagel, Republican Senator and a friend of McCain's, said her choice was an insult to the American people.
McCain, therefore, has a greater obligation, putting country first, to have that MRI because he chose Sarah Palin to be a heartbeat, or degeneration or metastasis away from the Presidency. McCain should also relinquish his privacy rights so that the MRI can be viewed by all of us.
Note: An MRI is safe and would take less than 30 minutes.