Their very first expedition had discovered the universe now designated "Alexandria-1," created by ART's "rescue" of the Great Library. Universe A1's True Present was nowhere near as technologically advanced as SysGov, and the scar the Library raid had left on its collective psyche would be hard to over exaggerate.
In many ways, finding A1 had been the final nail in the coffin of ART's time travel program. It had conclusively proved the model of transverse travel — and of the possibility of transdimensional fratricide — that Kleio's crew had devised. That had been enough to finish off any obstacles to the creation of Gordian Division, and aside from one or two TTVs designed for delving truly deep into Earth geological past, every one of its time machines had been handed over to Gordian.
Vice-Commissioner Schröder had continued the exploration process ART had begun, although he'd confined his efforts to the True Present, but he'd also been deeply involved in the debate over how to approach Universe-T2, the other time-traveling universe, controlled by the System Cooperative Administration. Some members of SysGov had favored just leaving T2 completely alone. After all, the Admin had done its level best to prevent Raibert and his team from saving his universe. Surely there would have been a certain poetic justice in letting them destroy their own?
Klaus-Wilhelm von Schröder had thought that was a terrible idea, for a lot of reasons. For one, it was virtually identical to the one from which he himself had sprung. More importantly, however, they couldn't know — not ahead of time — what would happen to any neighboring universes if one of them blew itself up. And that didn't even consider the billions of human beings – and star systems, and galaxies — which would share in the destruction.
But SysGov had been in no hurry, given how Raibert's first contact with that other Admin had gone, and so it had taken time to carefully consider how it would approach this Admin. During the time it spent thinking, Klaus-Wilhellm's survey teams had continued to spread out through the newly discovered multiverse — cautiously, given how little they yet knew about its structure and the Knot's evidence that humans truly could induce universe-ending catastrophes — and the TTV Kuebiko had been assigned to survey this one when it was discovered.
Kuebiko's crew had known they were stepping into a universe with an advanced human civilization, but no one back home had thought it was advanced enough for time travel. All that had changed when the they detected a foreign chronoton impeller coming online. The Kuebiko team had reclassified the universe as T4 — the fourth universe on record to have confirmed time travel — and then aborted the rest of their mission. They'd returned to SysGov to report their findings and would have received a follow-up mission, but both T3 and T4 assignments had been placed on the back burner. Instead SysGov had finally decided how it would establish contact with Admin and that Gordian Division would be given responsibility for transverse security as well as for policing time travel in SysGov's own universe.
Klaus-Wilhelm von Schröder had even better reason than most to distrust Admin, which was why he had devoted the lion's share of his resources — and personnel — to keeping an eye on their belligerent multiverse neighbor. It hadn't been until months after Kuebiko's initial visit (and months of the Gordian Division's ongoing expansion) that resources had begun to free up for proper surveys of T3 and T4.
Which was why Raibert now found himself looking down at the imagery of T3's population centers.
"So what's caught your eye?" he asked.
"This." Benjamin overlaid SysGov's Earth with T4's and adjusted the display to highlight the discrepancies. Then he zoomed in on a single North American city: what was still known in SysGov as Washington DC.
Raibert raised an eyebrow.
"Watch what happens when I pull up the construction dates for the oldest building still standing back home."
Numbers sprinkled over the city, and Raibert frowned. It took him a minute to realize where Benjamin was leading him, but when he did, both eyebrows shot up.
"Oh."
"Yeah. Interesting, isn't it?"
"Very."
Elzbietá crossed her arms and squinted at the display. After a moment, she shrugged.
"Okay, guys. I give up. What am I missing? The cities are laid out differently, but we already knew that would be the case."
"True." Benjamin nodded. "But it's how they're the same that's more interesting."
"All the modern thirtieth-century structures are different," Raibert said. "Which we expected, but some of the older structures are the same."
"Some," Benjamin agreed. "But not all."
"Such as?" Elzbietá asked.
"There's no White House."
"Okay," Elzbietá said cautiously. "That's significant. But it could just mean the divergence point for this universe is before its construction."
"Normally, I might agree, despite how early in Washington's history the White House was built in both our universe and the Admin's. But there are what look like the remains of the Pentagon."
"Is that what they called it?" Raibert chuckled.
"Yes, Raibert," Benjamin replied grumpily. "That's what they called it."
"Kind of a no-effort name, don't you think?"
Benjamin frowned at their team leader, then looked rather pointedly back to Elzbietá.
"Anyway. This isn't a case of the White House never being built. It's a case of its having been destroyed."
"Aha!" Elzbietá snapped her fingers. "So my clever husband scores again!"
"Well, that's my hunch, anyway."
"Feels like a good one to me," Raibert said, leaning back in his seat.
"And that's why I think we might want to deviate from our original plan," Benjamin said.
"How so?"
"Well, consider this. We know almost nothing about T4, and while our stealth systems are good, that universe has already surprised us once with tech we thought it wouldn't have. So any time we spend in its True Present is a risk."
"A small risk," Raibert stressed.
"Granted, but not zero. So what if we went back into T4's past, instead, and located the point of divergence? Really pinned it down precisely. That could tell us an enormous amount about T4's societies, just from the overlap with our own. Having a firm grasp of what history we [i]do[/i] share could even help us form a better strategy for making first contact in the True Present."
"That would probably save time in the True Present, too," Elzbietá pointed out. Raibert raised an eyebrow at her, and she shrugged. "Like Ben says, knowing their past will let us visualize their present government's — or governments', plural — response to our arrival. If we turn up, well-versed in their history and able to draw comparisons and connections with SysGov's past, it ought to really speed up the diplomatic nice-making." She grimaced. "I had embassy duty twice in the Navy. Hated it, both times. I'd just as soon spend as little time on that here as I have to."
"Hmmm." Raibert rubbed his chin.
"Plus it might shed some light on whether or not T3 and T4 are connected," Benjamin added.
"Ah." Raibert wagged a finger. "Another good point there."
