Grunting and straining, we untangled ourselves. Soon afterward, the exterior sounds of thrashing Macros vanished entirely. Judging by the instant silence that fell over the tank, I knew we had made it back under the protection of the dome.
“We’re inside, Colonel Riggs,” Marvin said.
“Kwon? How many of the enemy do we have on the hull?”
“I’m not sure,” Kwon said, swiveling his turret.
“They might be too close to see, but I’m not-wait a minute,” Sloan said.
He fired, but something went wrong. Instead of an intense light, a gush of heat and fumes from the chemical laser backwashed into the tank. Fortunately, we were in our suits or we would have been in trouble.
“Looks like my vents are clogged,” he said.
“Cease firing. We have to flush out the blockage. Everyone, keep your suits on.” I didn’t think any of them were dumb enough to open their helmets, but I gave the order as a precaution.
“I see one now,” Kwon said. “They are coming through dome, sir.”
I opened a channel to the marines in the troop pod. “Marines, I want you to get out there and clear the hull of this tank. Engage anything coming through the dome. We’ll provided supporting fire from here when you clear our vents.”
Kwon slid away from his turret and cranked open the top hatch.
“Where do you think you’re going, First Sergeant?” I demanded.
“With the men, sir. Could you man my turret?”
I heard the marines moving out below. The back ramp dropped with a crash and heavy boots pounded. There were flashes and snapping sounds almost immediately, as the marines engaged the enemy.
“Hold on a second,” I told Kwon. The tank was nearly finished as a mobile platform, but I wanted it farther from the edge of the dome. “Marvin, take us closer to the factory. Move slowly.”
The big gears ground and clattered. The tank was moving again, but I could tell the treads on the right side were failing. Marvin fought the controls, as the levers were only power-assisted. They gave a lot of feedback, I hadn’t had time to design anything more sophisticated. Macro design was basic and over-built. It reminded me of old-fashion Soviet designs. When in doubt about stresses and tolerances, Macros just carpeted an extra layer of steel over everything.
The big machine made it almost to the factory when I called for it to halt. All this time, Kwon had been manning his turret, but when we finally halted he scrambled for the hatch again. I knew he couldn’t wait to get outside and smoke a few of those machines personally.
“All right,” I said. “Sloan, you man your turret. Marvin, you man Kwon’s. Kwon and I are going outside.”
Everyone looked happy with these assignments, especially Sloan. I could tell by his wide-open eyes he’d been worried I would take him outside with the machines. I almost chuckled-maybe he was the smartest one of the bunch.
We didn’t get far before we were caught up in the firefight outside. Kwon threw open the top hatch, and used his repellers to fly straight upward. He was firing at something on the ground, I could tell that. I climbed out after him and took a leap to the ground. My rifle was in my hand and I had the trigger depressed before Kwon came down again.
“Take cover, First Sergeant!” I ordered. “Stop showboating up there.”
“Sorry sir,” Kwon said, letting himself drift down beside the tipping tank.
After a flashing firefight, my marines managed to drive back the ten or so Macro workers with lasers who’d followed us under the dome. The rest really didn’t have a chance. Without ranged weapons, they snipped at the air a few times with what looked like hedge-trimmers then went down in a storm of heavy laser fire. These new projectors were very effective. A one-second burst focused carefully on the thorax was enough to disable a worker.
There was a lull in the fighting after we’d killed all those we could see. My men stayed in whatever cover they could find, which consisted mostly of our tank’s battered hull and the indentation made by the treads. I threw myself down on my belly in a dished out section of earth and checked my weapon for damage. I had still had a ninety-percent charge and there was no sign the unit was going to overheat soon.
Kwon fell into the pit beside me, his heavy body tossing up a shower of dust. “The tank has taken quite a beating,” he said.
I followed his gaze. In spots, the tank’s two-foot thick armor was down to less than a foot of crispy, pitted metal. Much of the melting effect appeared to have come from directly above-which I assumed had been done by my own ships. They’d fried the Macros on our hull as I’d asked, but had almost overdone it and fried us as well. I had no doubt this was why the tank’s vents were clogged. They’d probably melted and fused together. I was surprised the two cannons operated at all.
Looking around the scene, I saw a trail of twisted metal wreckage that led from the tank to the edge of the dome. We’d been dragging them and crushing them down into the earth with every foot of progress.
“Why have they stopped coming, Colonel?” Kwon asked me.
“They haven’t,” I said. “Macros don’t just quit, not unless they are calling off the attack completely. I don’t buy that. Not yet.”
“Maybe our troops have come down outside, and are engaging them.”
I would have liked to talk to Miklos and find out just how close that was to happening, but I didn’t buy that argument either. I shook my head. “I don’t think so. It’s too soon for that. It will take a few hours for Miklos to get ground support down here.”
Kwon looked at me. “I see,” he said. “So we are on our own?”
“For now.”
Kwon looked back toward the perimeter. “Where are they? What the hell are they doing out there?”
“They are probably massing up just outside the dome. They’ll come inside all at once and try to overrun us.”
“Ah,” Kwon said. He grunted as he climbed to his feet. “In that case, we have a few minutes. What are your orders?”
I looked up at him, and stood up beside him. Kwon was so quick to accept my theories as facts. I wished I had a thousand more like him-but then, that might not have been healthy when I turned out to be wrong.
“Let’s dig in,” I said. “Set up trenches around the tank.”
Kwon brought a gauntlet to his helmet. “What if they come in under us, sir? Remember South America?”
“But they can’t…” I began, but then I trailed off. I nodded. “Right. They could be digging outside, coming in through the dome underground, then pressing ahead into the middle of this region. In fact, for all we know, there are tunnels under us right now.”
We didn’t have a surviving sensor box that could measure activity under our feet. I felt trapped. If we dug in, they might get in close and tear into our lines. If we stood on top of our single tank, we would be easy targets if they simply walked through the dome.
Finally, I turned and looked toward the idle factory itself. “We’ve got plenty of steel, at least. Let’s build something.”
This time, with Marvin’s help translating my instructions, I designed something more useful than a massive block of steel. I didn’t have time to make a new tank, of course. But I figured we could use a structure, a battlement of some kind that could not be dug under and yet would provide cover from incoming fire. Simple geometric blocks and flat planes of metal. Something that would come in sectional pieces we could fit together. This machine should be able to generate structures like that very quickly. The factory was the only asset I had, so I was determined to do the best I could with it.
Within a few minutes I came up with a series of metal planks, about thirty feet long each. These would fit easily in the output tray, and two of my men in their exoskeletal suits could lift and place them. Each plank of steel was four inches thick-enough to stop a laser bolt. I would have loved to have a barrel of constructive nanites to weld them together, but wishing didn’t make it happen. Instead, I ordered the steel planks to be made with holes drilled through at regular intervals. Then I ordered a large number of steel rods to be built at the same time.