What are we to make of President Barack Obama's latest pronouncements about Iran's movement toward nuclear bombs? His tough talk might have had some influence on Iran a couple of years ago, when he was instead being kinder and gentler with the world's leading terrorist-sponsoring nation. Now his tough talk may only influence this year's election -- which may be enough for Obama.

The track record of Barack Obama's pronouncements on a wide range of issues suggests that anything he says is a message written in sand, and easily blown away by the next political winds. Remember the "shovel-ready projects" that would spring into action and jump-start the economy, once the "stimulus" money was available? Obama himself laughed at this idea a year or so later, when it was clear to all that these projects were going nowhere.

Remember how his administration was going to be one with "transparency"? Yet massive spending bills were passed too fast for the Congress itself to have read them. Remember the higher ethics his administration would practice -- and yet how his own Secretary of the Treasury was appointed despite his failure to pay his taxes?

If you were an Israeli, how willing would you be to risk your national survival on Obama's promise to stand by your country? If you were a leader of Iran, what would you make of what Obama said, except that an election year might not be the best time to attack Israel?

Members of the Obama administration have been pointing out how hard it would be to destroy Iran's nuclear facilities, now that they have been built deep underground and dispersed.

That would have been something to consider during the time when President Obama was taking leisurely and half-hearted measures to create the appearance of trying to stop the Iranian nuclear program, while vigorously warning Israel not to take military action.

Time was never on our side. The risks go up exponentially the longer we wait. When the Iranian nuclear program was just getting started, it could have been destroyed before it became so big, so dispersed and so deeply dug in underground. Now, if we wait till they actually have nuclear bombs, the same kinds of arguments for inaction will carry even more weight, when the price of an attack on Iran can be the start of a nuclear Holocaust.

Nor should we assume that we can remain safe by throwing Israel to the wolves, once the election is over, as might well happen if Obama is re-elected and no longer has any political reasons to pretend to be Israel's friend.

That kind of cynical miscalculation was made by France back in 1938, when it threw its ally, Czechoslovakia, to the wolves by refusing to defend it against Hitler's demands, despite the mutual defense treaty between the two countries. Less than two years later, Hitler's armies were invading France -- using, among other things, tanks manufactured in Czechoslovakia.

This was just one of the expedient miscalculations that helped bring on the bloodiest and most destructive war the world has ever known. Dare we repeat such miscalculations in a nuclear age?

At the end of the Second World War, Winston Churchill said, "There never was in all history a war easier to prevent by timely action than the one which has just desolated such great areas of the globe." It might even have been prevented "without the firing of a single shot," Churchill said.

Early in Hitler's career as dictator of Germany, the Western powers -- indeed, France alone -- had such overwhelming military superiority that an ultimatum to Hitler to stop rearming would have left him little choice but to comply. But the price of stopping him went up as time went by and he kept on rearming.

When Hitler sent troops into the Rhineland in 1936, in defiance of two international treaties, he knew that Germany at that point had nothing that would stop the French army if it moved in. But France was too cautious to act -- and caution can be carried to the point where it becomes dangerous, as France discovered when a stronger Germany conquered it in 1940.

Churchill warned, "Do not let us take the course of allowing events to drift along until it is too late." But that is what expediency-minded politicians are always tempted to do.