diff --git a/include/sect.h b/include/sect.h
index 58f54775..7c6e338f 100644
--- a/include/sect.h
+++ b/include/sect.h
@@ -173,6 +173,9 @@ extern struct dchrstr bigcity_dchr;
 /* Work required for building */
 #define SCT_BLD_WORK(lcm, hcm) ((lcm) + 2 * (hcm))
 
+#define SCT_DEFENSE(sp) \
+    (opt_DEFENSE_INFRA ? (sp)->sct_defense : (sp)->sct_effic)
+
 #define MIN_MOBCOST  0.001	/* lowest cost a sector can have to move into */
 #define FORTEFF 5		/* forts must be 5% efficient to fire. */
 
diff --git a/src/lib/commands/bomb.c b/src/lib/commands/bomb.c
index 5c0c18e9..ef308d17 100644
--- a/src/lib/commands/bomb.c
+++ b/src/lib/commands/bomb.c
@@ -369,8 +369,6 @@ eff_bomb(struct emp_qelem *list, struct sctstr *target)
     target->sct_road = effdamage(target->sct_road, dam);
     target->sct_rail = effdamage(target->sct_rail, dam);
     target->sct_defense = effdamage(target->sct_defense, dam);
-    if (!opt_DEFENSE_INFRA)
-	target->sct_defense = target->sct_effic;
     pr("did %d%% damage to efficiency in %s\n",
        oldeff - target->sct_effic,
        xyas(target->sct_x, target->sct_y, player->cnum));
diff --git a/src/lib/commands/buil.c b/src/lib/commands/buil.c
index a46d4ee7..909a0026 100644
--- a/src/lib/commands/buil.c
+++ b/src/lib/commands/buil.c
@@ -615,8 +615,6 @@ build_bridge(struct sctstr *sp, short *vec)
     sect.sct_road = 0;
     sect.sct_rail = 0;
     sect.sct_defense = 0;
-    if (!opt_DEFENSE_INFRA)
-	sect.sct_defense = sect.sct_effic;
     if (opt_MOB_ACCESS) {
 	time(&sect.sct_access);
 	sect.sct_mobil = -(etu_per_update / sect_mob_neg_factor);
@@ -915,8 +913,6 @@ build_tower(struct sctstr *sp, short *vec)
     } else {
 	sect.sct_mobil = 0;
     }
-    if (!opt_DEFENSE_INFRA)
-	sect.sct_defense = sect.sct_effic;
     sect.sct_mines = 0;
     map_set(player->cnum, sect.sct_x, sect.sct_y, dchr[SCT_BTOWER].d_mnem, 2);
     writemap(player->cnum);
diff --git a/src/lib/commands/dump.c b/src/lib/commands/dump.c
index f36b2d20..af020b7f 100644
--- a/src/lib/commands/dump.c
+++ b/src/lib/commands/dump.c
@@ -733,7 +733,7 @@ dump(void)
 		pr("%d", sect.sct_rail);
 		break;
 	    case 71:
-		pr("%d", sect.sct_defense);
+		pr("%d", SCT_DEFENSE(&sect));
 		break;
 	    case 72:
 		if (opt_FALLOUT)
diff --git a/src/lib/commands/new.c b/src/lib/commands/new.c
index 29cc0bc1..c8dd174d 100644
--- a/src/lib/commands/new.c
+++ b/src/lib/commands/new.c
@@ -134,8 +134,6 @@ new(void)
     sect.sct_road = 0;
     sect.sct_rail = 0;
     sect.sct_defense = 0;
-    if (!opt_DEFENSE_INFRA)
-	sect.sct_defense = sect.sct_effic;
     sect.sct_mobil = startmob;
     sect.sct_work = 100;
     sect.sct_oldown = num;
@@ -159,8 +157,6 @@ new(void)
     sect.sct_road = 0;
     sect.sct_rail = 0;
     sect.sct_defense = 0;
-    if (!opt_DEFENSE_INFRA)
-	sect.sct_defense = sect.sct_effic;
     sect.sct_work = 100;
     sect.sct_oldown = num;
     sect.sct_mobil = startmob;
diff --git a/src/lib/commands/sinf.c b/src/lib/commands/sinf.c
index 48698384..23c09bf6 100644
--- a/src/lib/commands/sinf.c
+++ b/src/lib/commands/sinf.c
@@ -39,6 +39,7 @@
 #include "sect.h"
 #include "nsc.h"
 #include "nat.h"
+#include "optlist.h"
 #include "path.h"
 #include "commands.h"
 #include "combat.h"
@@ -78,7 +79,7 @@ sinfra(void)
 	pr("%4.3f ", sector_mcost(&sect, MOB_ROAD));
 	pr("%4d%% ", sect.sct_rail);
 	pr("%4.3f ", sector_mcost(&sect, MOB_RAIL));
-	pr("%4d%% ", sect.sct_defense);
+	pr("%4d%% ", SCT_DEFENSE(&sect));
 	pr("%5.2f\n", sector_strength(&sect));
     }
     if (nsect == 0) {
diff --git a/src/lib/commands/work.c b/src/lib/commands/work.c
index d84bcb4b..b7174e15 100644
--- a/src/lib/commands/work.c
+++ b/src/lib/commands/work.c
@@ -142,8 +142,6 @@ buildeff(struct sctstr *sp, int work, double *money)
 	    sp->sct_type = sp->sct_newtype;
 	}
 	sp->sct_effic = n;
-	if (!opt_DEFENSE_INFRA)
-	    sp->sct_defense = sp->sct_effic;
 	work -= work_cost;
 	*money += work_cost;
 	effdone += work_cost;
diff --git a/src/lib/common/sectdamage.c b/src/lib/common/sectdamage.c
index f0d2dadc..b1f2679d 100644
--- a/src/lib/common/sectdamage.c
+++ b/src/lib/common/sectdamage.c
@@ -65,8 +65,6 @@ sect_damage(struct sctstr *sp, int dam, struct emp_qelem *list)
     sp->sct_road = damage(sp->sct_road, dam);
     sp->sct_rail = damage(sp->sct_rail, dam);
     sp->sct_defense = damage(sp->sct_defense, dam);
-    if (!opt_DEFENSE_INFRA)
-	sp->sct_defense = sp->sct_effic;
 
     eff = dam;
 
diff --git a/src/lib/subs/attsub.c b/src/lib/subs/attsub.c
index a214372d..052aece3 100644
--- a/src/lib/subs/attsub.c
+++ b/src/lib/subs/attsub.c
@@ -349,8 +349,6 @@ put_combat(struct combat *com)
 		sect.sct_defense = 0;
 	}
 	sect.sct_effic = com->eff;
-	if (!opt_DEFENSE_INFRA)
-	    sect.sct_defense = sect.sct_effic;
 	if (com->mobcost) {
 	    if (opt_MOB_ACCESS) {
 		if ((com->mob - com->mobcost) < -127)
@@ -2606,7 +2604,7 @@ sector_strength(struct sctstr *sp)
 	d = 2.0;
 
     d = d + ((double)(dchr[sp->sct_type].d_dstr - d) *
-	     ((double)sp->sct_defense / 100.0));
+	     ((double)SCT_DEFENSE(sp) / 100.0));
 
     if (d > dchr[sp->sct_type].d_dstr)
 	d = dchr[sp->sct_type].d_dstr;
diff --git a/src/lib/subs/sect.c b/src/lib/subs/sect.c
index 4ad8390f..ffc235a5 100644
--- a/src/lib/subs/sect.c
+++ b/src/lib/subs/sect.c
@@ -132,8 +132,6 @@ checksect(struct sctstr *sp)
 	    sp->sct_mobil = 0;
 	}
     }
-    if (!opt_DEFENSE_INFRA)
-	sp->sct_defense = sp->sct_effic;
     return 1;
 }
 
diff --git a/src/lib/update/sect.c b/src/lib/update/sect.c
index eebf0165..887f1811 100644
--- a/src/lib/update/sect.c
+++ b/src/lib/update/sect.c
@@ -362,8 +362,6 @@ produce_sect(int natnum, int etu, int *bp, long (*p_sect)[2],
 		np->nat_money -= cost;
 		sp->sct_type = desig;
 		sp->sct_effic = neweff;
-		if (!opt_DEFENSE_INFRA)
-		    sp->sct_defense = sp->sct_effic;
 	    }
 	}