Politics is often like war. Unfortunately, politicians, the media and the voting public seldom have the same degree of realism and discipline with which professional soldiers fight wars. You can indulge your emotions and base your decisions on wishful thinking in politics, in a way that you are not likely to when your own life is on the line in battle.
One of the most dramatic and heartening events of World War II was the miraculous evacuation of British troops trapped on the beaches of France in 1940, at Dunkirk. And its lesson is still relevant today.
The British troops were in France to help the French fight off the invading army from Nazi Germany. But the sudden collapse of the French army left the Brits stranded on the beaches, with the German army closing in on them.
The British navy's ships in the area were too large to move into the shallow waters close to the beaches, so as to evacuate the troops. Instead, hundreds of British civilians headed for Dunkirk in their fishing boats, recreational craft and practically anything else that would float.
These civilians, who risked their lives going into a war zone, helped nearly a hundred thousand British soldiers get back home across the English Channel.
How does this tie in with politics, especially with politics today?
Many Republicans wanted their party to fight the Obama administration before agreeing to raise the debt ceiling, in hopes of extracting at least some concession - on spending, on the Keystone pipeline or whatever.
Unfortunately, the Republicans had no more chance of winning that fight than the stranded British troops had of winning a battle against Hitler's army.
Whatever the Republicans threatened, President Obama could call their bluff. They would either have to back down or have a second government shutdown for which they would be blamed. Another shutdown could doom their chances of winning the Senate in the 2014 elections, and perhaps even cost them the House of Representatives.
In a war, you do not fight battles that you are certain to lose, if only because you will need your troops to fight later in battles you can win.
The British troops who escaped from Dunkirk came back to France four years later, as part of the massive invasion forces that stormed the beaches at Normandy, liberated France and pushed on into Germany for the final defeat of the Nazi regime.
In politics, as in war, you need power to win, and you don't dissipate your forces fighting battles that you are sure to lose. Symbolism and emotional self-indulgence are just not worth it.
None of this says that the Republicans' leadership had a great track record prior to the most recent confrontations with the Democrats.
For that matter, the British government had a terrible track record in the years leading up to the desperate situation on the beaches at Dunkirk. But that was no reason to sacrifice troops who would be urgently needed for later battles, where the odds would be different.
There would not be a United States of America today if George Washington had followed the tactics being urged by people like Senator Ted Cruz and his supporters.
The army under General Washington was no match for the British army, in either military experience or firepower. The American army repeatedly had to withdraw, retreat and even flee to avoid being annihilated.
George Washington did not have to fight futile battles in order to prove his courage. He was already well known for being in the thick of battles, with bullets whistling around his head. But he had to wait for situations where he had the enemy at a disadvantage, and then strike.
When Washington made his celebrated crossing of the Delaware, he was headed for a dramatic victory, using soldiers he had saved for just such a moment. Wars are about winning, not futile symbolic gestures that leave you worse off. Politics must be the same, if you are serious about the issues.
Thomas Sowell is a senior fellow at the Hoover Institution, Stanford University.