For about a decade, American military commanders leading the fight against Al Qaeda, the Taliban and Saddam Hussein had a blank check from Congress to buy whatever weapons and other supplies they needed. Now, the Pentagon is being forced to live with less in a new era of fiscal austerity.

With the Iraq war over and troops coming home from Afghanistan, the military budget must be reduced. The question is whether we can be smart about it. The across-the-board approach dictated by the budget reductions known as the sequester — rapid, steep, indiscriminate cuts to both bloated programs and essential ones — is the wrong way to go, causing chaos and turmoil in defense planning. Commanders say the sequester has already affected military readiness.

The Pentagon’s base budget was cut $37.2 billion in April as a result of the sequester. Barring a compromise deal between Republicans and Democrats, the Pentagon will face an additional $52 billion cut in January, bringing the total budget for 2014 down to about $475 billion. Through 2023, the cumulative defense cuts could amount to more than $1 trillion, including the reductions already made.

Reality is sinking in. It was startling, for instance, to see that the Air Force told The Wall Street Journal that it is now determined to build a new long-range bomber, a replacement for the storied B-52s and B-1s, on a “budget.” The Journal reported that an Air Force manager for the $55 billion project killed a $300,000 kitchenette for the plane because the feature was too expensive. Meanwhile, the Navy has pledged to cut the costs of building the next aircraft carrier, the John F. Kennedy, by $1.2 billion.