Arguing for war to prevent war

It is interesting and challenging to read arguments for war which are based on the premise that the war will prevent a more dangerous war. I have previously touched on this, and have today been sent an article which comes to these very conclusions. How do we decide something like this, whose lives do we value, whose lives are we willing to sacrifice? Of course, war always raises this issues, but in this case it seems to be more immediate - though the author is not in power and so this is "only" an intellectual exercise at this point.

Below are the last few paragraphs of the article with a link - you decide for yourself.

"...The Obama administration tells us that the interim agreement puts Iran on a track that will lead to the abandonment of its quest for a nuclear arsenal. But the Iranians are jubilant because they know that the only abandonment going on is of our own effort to keep them from getting the bomb.

Adherents of the new consensus would have us believe that only two choices remain: a war to prevent Iran from acquiring nuclear weapons or containment of a nuclear Iran—with containment the only responsible option. Yet as an unregenerate upholder of the old consensus, I remain convinced that containment is impossible, from which it follows that the two choices before us are not war vs. containment but a conventional war now or a nuclear war later.

Given how very unlikely it is that President Obama, despite his all-options-on-the-table protestations to the contrary, would ever take military action, the only hope rests with Israel. If, then, Israel fails to strike now, Iran will get the bomb. And when it does, the Israelis will be forced to decide whether to wait for a nuclear attack and then to retaliate out of the rubble, or to pre-empt with a nuclear strike of their own. But the Iranians will be faced with the same dilemma. Under these unprecedentedly hair-trigger circumstances, it will take no time before one of them tries to beat the other to the punch.

And so my counsel to proponents of the new consensus is to consider the unspeakable horrors that would then be visited not just on Israel and Iran but on the entire region and beyond. The destruction would be far worse than any imaginable consequences of an Israeli conventional strike today when there is still a chance to put at least a temporary halt, and conceivably even a permanent one, to the relentless Iranian quest for the bomb."

http://online.wsj.com/news/articles/SB10001424052702303560204579246142096554348?mod=WSJ_Opinion_LEADTop

What do you make of the points raised? 

Some of the comments posted with the article are particularly insightful, though unfortunately many are hyper-partisan and worse.