But Joe Mackenzie appreciated little of this. Approaching sixty, Mac, a veteran of too many years in inner-city emergency departments and battlefield medicine, had become a walking, talking definition of cynicism, Maggie thought – even if there was nobody else she’d sooner have at her side on this first expedition of Armstrong and Cernan. And now his expression was stony.

‘I know what you’re thinking,’ Maggie said.

‘Do you?’

‘“What a damn circus.”’

‘That’s the polite version.’

‘Mac, this mission is kind of – complicated. We carry a freight of symbolism. The overt purpose of it is to go further stepwise than any ship before us, even those Chinese ships before Yellowstone. But the deeper meaning is that we’ll be a visible demonstration of the recovery of America – we’ll show that Americans can do more than just shovel ash. Mac, we’ll go down in history.’

‘Or in flames.’

‘And you’ll be there to salve the wounds as always.’

‘Look, Maggie, I know I’m a crusty old bastard. But as far as I’m concerned all this American-destiny stuff is a lot of hooey. Cowley’s only true objective for this trip is just as it was when we went out in the Franklin, all those years ago, when Valhalla was boiling up to rebel. To project federal power across the Aegis. To remind those uppity colonials and combers out there who’s boss. And as far as I’m concerned, our only worthwhile mission objective is to find what became of the crew of the Armstrong I.’

‘Fair enough. Glad to have you aboard anyhow. Oh, by the way, I’m bringing the cat.’

He flared. ‘God dammit, Maggie, why don’t you just stick pins in my eyes?’

Suddenly, shadows from the sky striped across the square.

Maggie tipped up her head to see, and shielded her eyes. Precisely at noon, three airships had appeared above their heads.

The two brand new Navy craft, the USS Neil A. Armstrong II, and the USS Eugene A. Cernan, were whales in the sky. Their predecessors, including Maggie’s own old command the Franklin, based on Long-Mississippi commercial twain technology, had been a little smaller than the venerable Hindenburg. The new Armstrong, like its sister, was nearly half as long again, topping out at more than a thousand feet from stem to stern, not counting a protruding comms antenna and massive tail planes mounted with compact jet engines. The crew liked to brag about how that great envelope could swallow the old Franklin whole, though that wasn’t quite true. But, with Cernan, the ship had taken the record for the largest flying machine ever constructed from the old Hindenburg. Mac had counselled Maggie not to boast too loudly about that, because after all the Hindenburg had been bankrolled by the Nazi party, and ultimately had crashed and burned . . . Maggie had pored over the engineering details as the ships had been designed and constructed, like a kid in a toy store. Now her heart swelled with pride that two such magnificent ships were hers to command.

And between the Navy ships, stepping in at precisely the same moment in a neat bit of synchronization, was a smaller ship but just as sturdy-looking, its hull painted white and blue with a proud presidential seal emblazoned on its flanks and tail fins. Popularly known as Navy One, this twain was the President’s own dedicated craft, heavily defended and bristling with armour and, it was rumoured, luxuriously appointed within.

Now, with a hum of powerful engines, a soft downwash of air and some neat navigation, Navy One descended towards the Capitol building, and a hatch in the base of the gondola opened up to allow a staircase to extend smoothly to the stage.

With secret service agents front and back, the unmistakable form of Brian Cowley came down the ramp. The band struck up ‘Hail to the Chief’, there were good-natured cheers from the gawking crowd out beyond the perimeter, and Cowley worked his way along the line of dignitaries with handshakes. He was an overweight man in a crumpled suit.

Mac grunted. ‘Look at him with Douglas Black. Jeez, that’s not a handshake, that’s a transfer of DNA. Get a room, Mr President.’

‘Now, now, Mac. Scuttlebutt is that Black bankrolled the building of these ships, the whole damn expedition. You can’t begrudge him his moment in the spotlight.’

‘Yeah, but he probably bankrolled the spotlight too . . .’

At last Cowley stepped up to the microphone, and grinned at the gathering before him. ‘My fellow Americans, and people of the planet Earth – all the planet Earths . . .’

He had always had the easy, graceful command of a natural orator – well, his whole career had been predicated on that one skill – and as his gaze swept over her, Maggie felt herself swell with pride, just a little. Asshole the man might once have been, and might still be, but he was the President, the office was always greater than any one man – and since Yellowstone Cowley had demonstrated that there had been far worse incumbents before him.

Now Cowley looked up at the new vessels, hovering above the Capitol. ‘Beautiful new ships, aren’t they? The product of American technical ingenuity, and the generosity of our own people and our partners from overseas.’ He pointed. ‘Neil Armstrong. Eugene Cernan. I’m sure you all grew up knowing the first of those names. But what of the second? I bet you looked it up before you came out here today.’ A ripple of laughter. ‘So you see, the names are kind of fitting. And I want you to think of the mission I’m launching today as being a Project Apollo for our generation. This is our moon shot – and let me tell you, it’s a hell of a lot cheaper!’

After his reward of a little more laughter, he referred back to earlier heroes of exploration: Lewis and Clark, who in the early nineteenth century, under instructions from President Jefferson, had mounted an expedition to survey the peoples and resources of the vast territories acquired by a young America from Napoleon in the Louisiana Purchase, and to establish a route to the Pacific coast. Now, like Lewis and Clark, Captain Maggie Kauffman would lead her ships West, out into the far stepwise reaches of the Long Earth, exploring the footprints of America, mapping, making contact, laying claim.

Mac growled, ‘During the re-election campaign he was Roosevelt. Now he’s Jefferson. Thinks big, doesn’t he?’

‘They go to see what’s out there,’ Cowley said ringingly. ‘They will go, not two million steps like Joshua Valienté fifteen years ago, not twenty million like the great Chinese mission of discovery five years ago – their target is two hundred million Earths, and more. They will map, they will log, they will study, and they will plant the flag. They go to find out who’s out there. And they go to extend America as far as the footprint of this great nation can be said to exist. And, if it’s humanly possible, they will bring home the lost crew of the Neil Armstrong I, lost all these years . . .’

Cheers and whoops.

Mac grunted sourly. ‘This from the man who used to claim stepping folk were either demons sent by the devil or a species of subhuman.’

‘We all make mistakes,’ Maggie whispered back with a grin.

Now Cowley was growing more reflective. ‘Our nation has suffered a great blow. We all know that; only the very youngest among us cannot remember the time of plenty before Yellowstone, which we compare to the deprivation of the present. Well, recover we will, as the might and resources of the new worlds of the Long Earth come to the aid of the old . . .’

He was battling to be heard now over the predictable cheers.

‘This is a time of recovery from disaster. But it is also a time of coming together, of a rebuilding of strength. A time that will be remembered as long as humanity survives. I say to you young people gathered before me: go out in these great Arks of the sky. Go out into the new worlds God has given us. Go out there, and found a new America!’