Pres. Obama is our armed forces' Commander-in-Chief.   He is sworn to defend America against all enemies, foreign and domestic.  He must decide which are the greatest threats to America, and how best to deal with them.   If he decides incorrectly, or fails to decide in good time, many Americans will die. 
     The greatest threat is still nuclear annihilation.  While this threat has receded greatly since the collapse of the Soviet Union, it remains real.  Aside from Russia and Communist China, either of which could adopt a hostile policy leading to an attack on America under a future government, there is the prospect of atomic bombs in a few years--or perhaps months--in the hands of the Ayatollahs of Iran, and the fact of hundreds of atom bombs in the hands of the government of Pakistan this moment.  And who will be the government of Pakistan tomorrow?  A clique of corrupt generals? A party of America-hating socialists?  Or the  Taliban? 
     The nuclear age has changed the world forever.  We can never go back to 1944.  Since 1945 we have become complacent: A-bombs have been controlled by the very few governments that possessed them--The USA, Britain, France, Israel, India,  USSR, and post-Mao China. These governments were either democratic and peaceful, or at least sane and rational.  Even if hostile and ruthless, they did not expect to launch a nuclear war against the United States and survive, let alone be greeted by 72 virgins in heaven. 
      The same cannot be said for the salafi moslem fanatics, both sunni and shia, who lead Al Quaeda, Taliban, and Iran.  If they acquire A-bombs, it is more than merely a simple matter of 'nuclear proliferation'.  This term itself is dangerously disingenuous, suggesting as it does only the increase in the number of governments possessing A-bombs, without any hint of the horrendous consequences of the increased likelihood of their actual use.
     Mankind would be better served by using the term 'Hiroshima roulette'; up until recently, there were no governments in possession of A-bombs who were not either democratic and peaceful, or effectively deterrred by the huge preponderance of nuclear arms in the hands of  NATO (USA, Britain, France) and the certainty of massive retaliation against any aggressive use of  nukes or other WMDs.   The nuclear revolver was effectively empty.  But since the acquisition of  A-bombs by Pakistan and Communist North Korea, there are at least two bullets in the cylinder, and Iran will make three.  If any of these governments deliver A-bombs to the terrorist groups they currently use as cut-outs for their war of jihad against the infidels, that will be equivalent to pulling the trigger on a loaded chamber.  This is a game in which time is not on the side of 'peaceful coexistence' as it was in the latter days of the cold war.  From now on, every year that passes is equivalent to another pull of the trigger....
     I have already described how we can prevent the ayatollahs of Iran from acquiring their nuclear toys ("How to Defend the USA Against a Nuclear 9-11").   Let us consider the equally urgent, although much less talked about, threat from the 200+ A-bombs in the uncertain hands of the Pakistani Army.  These weapons, or even a fraction of them, could utterly destroy the United States as a civilized nation--if they were to be detonated in American cities. 
     The Pakistanis have neither missiles nor bombers with sufficient range to deliver them to the USA.  This, however, is irrelevant.  They do possess shipping containers and commercial airliners capable of transporting A-bombs, and 10 tons of lead shielding, (to prevent detection by geiger counter) to any port of entry in the USA.   We currently inspect only about 1% of all incoming cargo, and our ultimate goal is to inspect, someday, only 7%.  
     Pakistan today is locked on the path to civil war, not because of our presence in Afghanistan but in spite of it.  The Taliban was created initially (in the 1980s) by Pakistani religious jihadi fanatics of the deobandi sect, funded by sympathetic co-religionists in the Pakistani armed forces and Inter-Service Intelligence (ISI) and the Wahabi fanatics among the Saudi royal family.  Whatever the motives of the Pakistani backers of the Taliban, like Dr. Frankenstein they now find themselves utterly unable to control the monster they have created.     
     The Taliban, and their Arab allies in Al Quaeda, are no longer confining their insurgent terror to Afghanistan; for the last several years, they have become more and more murderous and wide-ranging in Pakistan itself, and have often announced their intention of 'islamizing' Pakistan, creating a Taliban-ruled sharia government there just as in Afghanistan.  This is a threat which the ruling elite in Islamabad still refuse to oppose  seriously, in spite of public pronouncements  and highly publicized  military sweeps of Taliban country in Waziristan, largely for the purpose of getting favorable press and plenty of  foreign-aid $ in the USA. 
     The possibility of a Taliban take-over of a Pakistani nuclear arms depot--or even of the entire country in a few years--cannot be discounted.  If the USA withdraws from Afghanistan, or simply fails to defeat the Taliban, allowing Kabul to become a replay of the horrendous disaster that was Saigon in April 1975, with our allies being massacred by our enemies, the Taliban will quickly consolidate their power in Afghanistan and turn their gunsights on Pakistan.  The outcome of such a Pakistani civil war cannot be predicted with certainty, but the death toll can be: it will be in the millions.
     Let us remember what is at stake:  if terrorists can get their hands on one bomb, they can get 20--or 50.  These bombs can then be detonated in as many American cities, simultaneously, one fine Sunday morning.   This is the means of creating a 'world without America'---as Mahmoud Ahmedinejad has called on America-haters the world over to dream of, and work for.  And if the last hundred years teach us anything, it is that nothing is too horrible to be done by human monsters. 
     Whatever strategy or grand strategy our military and political leaders decide to employ in the war against the Taliban and Al Quaeda, they--and we--must be under no illusion that this is a 'war of choice' that we can simply choose to walk away from without condemning a huge number of Americans to a horrible death--not just soldiers in foreign lands, but Americans of all kinds, here in America; and not just thousands, as on 9-11, but millions.   This is a war we must win, however many troops are needed, and whatever sacrifice is called for to support those troops, who are, after all, fighting and dying to protect both us, and our friends and allies in foreign lands. 
     This is the decision that was made last year by Pres. George W. Bush, leading him to send 20,000 more troops to Afghanistan (the last are arriving there only now), a decision that was reconfirmed by the panel led by Bruce Reidel in March of this year when reviewing our policy at the request of Pres. Obama, and which has been reconfirmed most urgently by Gen. MacChrystal in his August report on the war, and by Secy. of Defense Robert Gates.  
     Barack Obama must now make a decision.  For the first time in his brief career as Commander-in-Chief---but not for the last---he must decide whether to  heed the advice of his military and civilian defense experts, and pursue a policy of victory, or a policy of 'compromise' (read 'appeasement') with the 'moderate Taliban' (the ultimate oxymoron!).
     Pres. Obama has said, a propos of Afghanistan and war in general, that he is "not comfortable with the concept of  'victory', it suggests Hirohito surrendering on the battleship Missouri."  [Actually it was the Japanese Foreign Minister, not Hirohito, who signed the surrender.]  The American who received that surrender, Gen. MacArthur, later observed that:  "In war there is no substitute for victory."   Let us pray that this will be Obama's choice.