Crush Depth

“Stealth so far, yes, out of necessity. But the whole point is the last line is the last line. Once we cut it we’re through the ANZA Gap, into the Pacific and free, where more clandestine tenders wait for Voortrekker.”

“More reloads, you mean, more missiles and torpedoes?”

Bauer nodded. “The problem of submarines is that when properly used they stay invisible. Yet High Command wants to send an unmistakable message to Asia and the rest of the globe. The Axis is winning, the Axis is on the march, look at our chain of mushroom clouds, the self-infatuated U.S. is puny and finished…. Thus, the last step tomorrow will be to make some noise.”

“How? Where?” Van Gelder was horrified, and angry.

Bauer read his face and chuckled. “Ah. You figured it out. You come with us as the rules-of-engagement man. The Americans have sent a submarine’s first officer more than once. We can’t let ourselves be viewed by world opinion as lagging any in our humanitarian care and concern for native populations.”

“You mean I have to go with you and help set off an atom bomb.”

“That’s exactly right.”

Van Gelder knew he looked distressed. Bauer had cynically ambushed him with a terrible but unspoken moral dilemma: Up to now, every target Voortrekker attacked had been purely military. But Bauer kept referring to civilian casualties.

Bauer fingered the butt of the pistol he always wore on a belt holster. Seated shoulder to shoulder, Van Gelder saw Bauer’s pupils narrow — a physical sign of aggressive intent impossible to fake.

“I’m sure I needn’t remind you, First Officer, that cowardice in the face of the enemy is punished by death.”

Damn you to hell, you high-ranking German thug. “I didn’t say I wouldn’t do it.”

“Good, good. You’re supposed to be the contrite one. That’s the whole idea. We Kampfschwimmer do all the real work, exploding things.” Bauer eyed Van Gelder up and down. “I’d prefer a man of sterner stuff, but you’ll do.”

“Don’t push me, Commander, sir. I’ve seen plenty of nuclear combat.”

“Yes. I heard. And Challenger got away.” Bauer tut-tutted sarcastically.

Now Van Gelder was truly livid…. He realized this was Bauer’s goal: anger displaced Van Gelder’s natural fear of the upcoming mission.

But Van Gelder still had serious doubts. “Is this thing really authorized? Or are you some kind of rogue?”

“A rogue? No. I’m working under written orders from Berlin, with enthusiastic concurrence from your government in Johannesburg. The whole thing’s a joint operation. Your captain has seen the orders, I assure you.”

“And I was kept in the dark.”

“Now you’re in the bright shining light with the rest of us. And don’t think I’m dragging you along just to assure your skipper won’t abandon us if something goes wrong.”

“You seem to be too good at reading my mind.”

Bauer gave a conciliatory shrug. “We’re both naval officers, you and I, and professionals. Remember, this is all grand strategy, high planning to win the war. You’ll be a hero, Van Gelder. You’ll win medals, you’ll personally help cement the bond between South Africa and Germany.”

Van Gelder grunted. This son of a bitch is using my own devotion to duty and love of country against me. The worst of it is, from a patriotic perspective he’s right.

“Besides,” Bauer said, “Jan ter Horst won’t command Voortrekker forever. He has his eyes on much bigger game, in the Boer regime in Johannesburg. Do a good job on this special mission tomorrow, and you’re one step closer to getting promoted. You do want Voortrekker yourself, don’t you, some day soon?”

Van Gelder nodded grudgingly. Bauer sure knows how to push my buttons.

“Timing is very important, to keep up the psychological pressure on the enemy and on neutrals after the New York and Diego Garcia raids. So don’t shit yourself. Adjust to it fast. The device we’ll use is tiny, less than half a kiloton. Just enough to destroy a hardened land node in the last leg of the SOSUS.”

“All right. You’ve made your point…. Will we face much opposition?”

“No trained troops, just local militia, and a lot of them are aborigine coloreds…. A godforsaken place called Chatham Island. A pushover.”

Twenty-four hours later, on Challenger

As Jeffrey watched in the control room, Commodore Wilson read the latest data assessment relayed to Challenger from the central SOSUS processing center via Ilse’s land-to-sea communications downlink. The live feed from sound-surveillance lines went first to the processing center, for detailed interpretation. Reports from there were radioed to Ilse on Chatham Island. Then she worked an acoustic array that sent the reports on to Challenger, deeply submerged. Ilse’s local sonar-based downlink was needed because no radio waves — not even extremely low-frequency ones — could penetrate thousands of feet of seawater and have any useful bandwidth or baud rate.

Not for the first time, Wilson frowned as he read the report. Jeffrey felt frustrated too. Jeffrey knew that a lot of this local SOSUS infrastructure had been cobbled together hastily since the outbreak of the war — maybe too hastily. Jeffrey ran the different steps of the process through his head, picturing what could go wrong at each stage.

The supercomputers outside Sydney, Australia, manned by U.S. Navy specialists, were busy digesting raw inputs from all the lines of SOSUS hydrophones. Jeffrey knew the inputs from the more distant lines were passed along to Sydney by satellite link, for redundancy in case of equipment failure or attack. Breaks in the undersea feed lines weren’t unknown — sharks sometimes tried to bite right through them, so they had to be buried and armored.

One ground station for this satellite relay network was built at a point where the northernmost hydrophone line’s main fiber-optic cable made landfall, on Chatham Island. The satellite loomed high overhead in geosynchronous orbit, a tenth of the way to the moon — which should be beyond the range of Axis antisatellite rockets and lasers. To try to tune out enemy jamming from off to the sides — based in Axis-held territory away from the ANZA Gap — the antennas that sent the radio beams back and forth through space were tightly focused.

Ilse was secretly using that same satellite link in reverse, to get key information covertly from Sydney. She passed the intelligence — radioed via the satellite — down through the ocean for Wilson’s consumption, using a line of special microphones strung into the deep by Clayton’s SEALs. But for good effective range and proper data reliability, Ilse had to constantly adjust for oceanographic conditions. Temperature and salinity at different depths, currents and tides and wind and waves and background noise, all varied over time. They’d degrade her signal badly if ignored. This was what she’d been trained for in the Aleutians off Alaska.

Jeffrey thought the whole thing sounded great, in theory. He wondered whether in practice it was functioning at all.

“We should have heard something by now,” Wilson stated.

“Concur, sir,” Jeffrey said. “Unless ter Horst is traveling a lot more slowly than we thought.”

“No. Sessions and I went over all the routes he could have taken. You saw our calculations, our time-and- motion estimates.”

“Maybe he wants to wait, so our side lets our guard down.”

“Emphatically negative, Captain. Think about it. The longer he hangs back from the SOSUS gauntlet in the ANZA Gap, the more nuclear subs we could free up from other duty and vector in, and the more Australia and New Zealand can strengthen their minefields and other defenses. The more time ter Horst allows to pass before his next attack, the more our embassies abroad can reclaim the initiative against the diplomatic repercussions of the Diego Garcia catastrophe. As far as ter Horst’s supposed to know, if he gives enough time, we could be here standing in his path.”

“What do you think we should do?”

“Launch your minisub again. I want you to go to the island in person, and report to me over the link.”

“Yes, sir.” Jeffrey gestured to Ensign Harrison to get the mini ready — Harrison had already made two trips to