Not only is the Washington Redskins' defense ranked last in the NFL, but it also seems to be suffering from an identity crisis.

Is the unit going to attempt to fix its problems by trying to be an aggressive, attacking defense that smothers opposing offenses, or by trying to be a bend-but-don't-break defense that hopes offenses fizzle on their own? The Redskins acknowledge they are frustrated in their search for answers, and part of the search appears to be trying to determine which approach best suits the club's personnel.

It is a defense looking for its personality. That doesn't explain why the unit struggled in the first half of the season, because the Redskins have tried both approaches--and others in between--without success. But their struggles underscore just how difficult it will be for the defense to get better in the second half of the season. Although the Redskins have six former first-round draft choices as starters (all four defensive linemen, plus cornerbacks Darrell Green and Champ Bailey), perhaps the parts simply do not fit together.

"Right now we're scrambling for answers," tackle Dan Wilkinson said this week. "We have the last-ranked defense. That has caused questions not only in the coaches' eyes, but in the players' eyes as well. Whenever you've struggled like we have, that's the natural thing to have happen. We're just not sure what it takes to get this thing turned around."

Green hinted Tuesday that his skills are being misused, saying he is not as comfortable or effective in zone coverages as he is when he is permitted to cover wide receivers man-to-man. Wilkinson hinted Wednesday that he also is being misused, saying he would prefer more freedom to push forward in pursuit of quarterbacks and ball carriers.

Defensive coordinator Mike Nolan began training camp saying he wanted the unit to have a relentless, aggressive style this season. That didn't work early in the season, and the Redskins have used a more conservative approach at times since. Still, Nolan says he wants the defense to get back to an attacking style.

"We want to be what we started out wanting to be," Nolan said. "I'm not getting off that track. You want your pressures [blitzes] to work, and you want your four-man rushes to look like pressures."

During the preseason, it appeared that the Redskins could have a dominating defense. Then, the thinking was that Green and Bailey could cover opposing receivers one-on-one, freeing up manpower up front for blitzes. Against the run, the thinking went, the line would hold its own, and the club's youthful, athletic set of starting linebackers would fill the creases and make the tackles.

It looked good during a preseason in which the starting defense yielded only six points in seven quarters. In the first half of the regular season, however, the Redskins surrendered 27.8 points and 402.3 yards per game. They are ranked last in the league against the pass and 26th against the run.

At its current pace, the Redskins' defense would surrender 6,436 yards this season. That would be the second-highest single-season total in league history. The record belongs to the 1981 Baltimore Colts, who allowed 6,793 yards and went 2-14.

Why has the original plan failed? The Redskins talk about mental errors, missed assignments and blown coverages. Blitzes have been with one linebacker or one safety at a time, not with the sort of numbers that overwhelm an offensive line and leave someone unblocked en route to the quarterback.

Others around the league say the defensive parts simply don't mesh. Several scouts said this week that, even though Green perhaps has lost a step at age 39 and Bailey makes rookie mistakes, virtually any team in the league would love to have them at cornerback because they allow a club to cover receivers man-to-man and blitz. The problem for the Redskins has been that when they have blitzed, they haven't gotten to the quarterback often enough. They don't have a dominant pass rusher on the line or a big, fast blitzing linebacker, and no cornerback can continue to cover a receiver one-on-one for an extended period when a blitz fails.

Bill Arnsparger, the longtime NFL defensive expert who was hired by the Redskins last month to assist Nolan, says he thinks the solution is to keep offenses guessing.

"You can't play the game any one way," Arnsparger said. "You have to mix your coverages. That means some zone, some man and some blitzes. If you do too much of any one thing, the offense can control you."

The defensive line, particularly Wilkinson and fellow tackle Dana Stubblefield, has been criticized for the club's inability to stop the run. Redskins officials maintain, however, that the defensive line is playing relatively well, and several league scouts echoed that. For the pair's combined $57 million contract, the Redskins perhaps have the right to expect them to do more than occupy blockers and create opportunities for others to make tackles. But that essentially is their job, and many observers insist they are doing it.

"Looking at films, week in and week out, no matter who we play, guys are not getting pushed around," Wilkinson said. "We're not getting pushed off the ball. . . . Most of the teams that run on us, they sit back there and pick their holes as they stretch our defense."

The Redskins knew when they decided to go with Shawn Barber, Derek Smith and Greg Jones as their starting linebackers that the inexperienced trio would make mistakes.

"We have a lot of young guys at real crucial positions," end Marco Coleman said. ". . . At this point in the season, you would think we'd have it together. But sometimes, we're just not where we're supposed to be."

Will the Redskins actually be better on defense in the season's second half? Because their next three games are against relatively weak offenses, they probably won't know until they play in Detroit on Dec. 5, in Indianapolis on Dec. 19 and at home against the Miami Dolphins on Jan. 2.

"We're getting better," Arnsparger said. "We've improved against the run. We need to improve against the pass. You just have to continue to work on the things that will make you successful."