By Steve Silverman-

(CBS) Offensive football is a great thing.

When Jay Cutler throws touchdown passes to Devin Hester and Brandon Marshall and the Bears roll to a one-sided victory 34-18 over the Dallas Cowboys on Monday Night Football, there’s room to celebrate.

But the most important aspect of the game and the thing that Bears fans can take to the bank is that the defense is hitting on all cylinders and will keep them competitive in the coming weeks.

The Bears have plenty of age on defense. Brian Urlacher, 34, is an old man who plays football. He’s still effective, but he is no longer gameplan-wrecking missile who would torpedo himself all over the field.

Julius Peppers, 32, has been a dominant player in the NFL long before he got to Chicago. He’s a magnificent pass rusher who stalks the quarterback each game. Can he be stopped? Only if opponents double-team him on every play like the Cowboys did Monday night.

That gave Lance Briggs, 31, the chance to step into the starring role and he did not hesitate. Briggs made the hero play when Tony Romo attempted to shuttle the ball forward and Briggs alertly picked it off and went 74 yards for a touchdown. That was the fourth touchdown of his career and his first since 2005.

Of course, Briggs wasn’t the only Bear with a touchdown return on an interception. Charles Tillman, 31, had the first score of the game when Bears pressure forced Romo into a quick release towards the sideline that Cowboys receiver Dez Bryant did not understand. Tillman knew Romo was making a hot-read throw even if the receiver didn’t. Tillman caught the ball and walked into the endzone.

That core group of four players are all on the wrong side of 30, and so is defensive lineman Israel Idonije, 31.

You’re not supposed to win with an older defense in the NFL. Players slow down and they can’t play with the speed they had showed in earlier years.

Five starting players who are 31 or older? That’s usually a recipe for disaster.

But that’s not the case with the Bears. Urlacher is not the same player he was, but it seems that his teammates have rallied around him. The same knee that kept him off the practice field during training camp doesn’t let him change direction as swiftly as he did in his prime.

Urlacher can go hard in one direction and he was credited with four tackles against the Cowboys, with one for a loss. But the days of him going sideline to sideline to make the big hit are gone.

As Urlacher’s physical contribution to the defense slows, Henry Melton’s pace increases. Coming home to Texas proved to be a party for him. Melton, 25, can bring pressure and collapse the pocket. His early sack of Romo helped set the tone. Perhaps the former Texas Longhorn was inspired by the homecoming.

Strong safety Major Wright is another former Texas star who enjoyed the bright lights of Jerry Jones’ palace. He made five tackles, but it was the two interceptions that pumped up defensive coordinator Rod Marinelli.

Marinelli and Lovie Smith don’t disguise their defense. They are not blitz-happy like so many other NFL teams. They dare opponents to beat them physically.

It’s not necessarily hard to figure out, but it is hard to beat. The Bears think they have a defense that will win the battle because they are stronger and faster than their opponents.

When it works like it did in Dallas last night, the Bears look like world-beaters who can challenge the Giants, 49ers and Packers for NFC superiority.

When it doesn’t, the Bears are an aging team that is running out of time.

There’s 12 weeks of a long season left to get the real answer.

There’s no doubt that there must be a consistent level of production from the offense. But it’s still the defense that must fire on all cylinders for the Bears to reach the heights this season.

steve silverman small Silverman: Defense Remains Key To All Bears Success

Steve Silverman

Steve Silverman is an award-winning writer, covering sports since 1980. Silverman was with Pro Football Weekly for 10 years and his byline has appeared in the Wall Street Journal, Playboy, and The Sporting News. He is the author of four books, including Who’s Better, Who’s Best in Football — The Top 60 Players of All-Time. Follow him on Twitter (@profootballboy) and read more of his CBS Chicago columns here.

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