We Will Destroy Your Planet (8 page)

Those of you not arriving in ships would be advised to follow that protocol also; build bunkers into and under hills, for the same reason. Maintain weapons emplacements and guard posts on the surface above, against encroaching ground forces, and be sure to maintain the high ground. Also be sure to install anti-aircraft systems, either in the form of missiles, automated weapons, or energy weapons. However you arrived, if you have the ability to cloak your ships and facilities, do so. Also always be sure to make use of whatever force shield technology you have.

Once you are firmly settled on the surface of the planet, it will be time to conduct operations, both military and objective-related, on the surface.

Once your landings have been made, and bridgeheads consolidated so that you can reinforce as necessary, you will be able to begin expanding out from these footholds. You will now be looking at moving around through the Earth's different environmental conditions, and seeking out further objectives to be secured.

Whatever your ultimate aim for the planet, you will now have to be able to work and fight on the surface, in the sea, and in the atmosphere. This means you will require vehicles and equipment, and will need to be prepared for a wide variety of climates and varying conditions in the zones of different types of operations to be conducted.

You will also need to be aware of various environmental situations, and not just those related to active resistance by the natives. It's a jungle out there – and desert, ocean, glacier, veldt… You must be prepared to live, thrive, and survive in all of these different types of environment if you are to seal your conquest of the planet.

Before discussing vehicles, you will need to be sure that your forces can withstand the terrestrial environment when outside of any vehicles. You may need pressure suits, if you evolved in a world with a thinner or denser atmosphere, and breathing equipment if the Earth's atmosphere is not conducive to supporting your form of life.

If you have come from a world with a lower gravity, or are adapted to life in microgravity aboard space vessels, you will probably require support structures for your physical form – limbs and spine, if you have them, for example – in order to withstand long periods on the surface of the Earth. Conversely, if you come from a higher gravity planet, you may find that there are degenerative side effects to being in a lower gravity environment for a long time, though you will probably have already discovered and addressed this issue while becoming adjusted to space travel. (But, see also the chapter on ‘Looking After Your Humans'.)

Even if you have encountered the issues of physical degeneration in microgravity, do not assume that these factors cannot still affect you on the surface of the Earth, if you originally came from a location with higher gravity. In such an instance, you may be tempted to assume you will be physically stronger than the natives of a lower gravity planet, but this is not necessarily the case, if your physiology is adapted for load-bearing rather than leverage.

Most of the inhabited regions are temperate in nature, neither too hot nor too cold, though even these areas can reach temperatures over between -25C and 35C at the extremes of the seasons.

Humidity, the amount of water vapour suspended in the air, varies wildly according to location, weather, time of year, type and amount of vegetation, topography, and a host of other factors. In general, areas with large amounts of trees and rainfall will have high humidity, especially in summer. This is particularly the case in regions around the equator, bounded by the tropics at 23 degrees north and south of the equator. This belt is a side effect of the Earth's axial tilt, resulting in the area within being able to have the Sun directly overhead at least once during the terrestrial year.

Because this band around the planet has the most direct sunlight, it is home to both the most humid forested areas, and the hottest deserts. On Earth, a desert is defined as an area that receives less than 10 inches of precipitation each year, which, while generally taken to mean arid hot areas, also means that most of the southern polar ice cap qualifies, as it is too cold there for precipitation. These different kinds of deserts have the highest and lowest temperatures on the planet. Within the past hundred years, Death Valley, an area of the Mojave Desert, and the lowest (below sea level) dry land point on the planet, has been known to reach almost 57C, while Antarctica has seen temperatures as low as -89C.

At sea level, on the surface of the Earth, the atmospheric pressure is 14.7 pounds per square inch (psi), called one bar by human scientists (actually, though, it's really 1.013 bar).

This pressure varies both with height above, and depth underwater. Obviously the increase in pressure underwater is more noticeable because water is denser than air, but the differences are considerable at both extremes. Underwater, the pressure increases by one bar for every 33 feet below the surface, due to the sheer mass of the surrounding water. If you have been conducting deep-sea operations, even within pressurized vehicles, you will have to return to the surface in stages. The same applies if you are a native oceanic species that has arrived in the sea and intend to invade the land. This is because, as the pressure decreases, gas bubbles will form in blood and cell structures, which can lead to a most painful death – occasionally by explosion.

Thankfully the differences between sea level and higher altitudes are not quite so extreme.

Above sea level, the atmospheric pressure decreases on average by about 10% for every three thousand feet, though this also varies according to local weather systems that disturb the atmosphere. The lower the pressure drops, the lower the temperature needed for liquids to boil, so if your species has a high liquid content, or dependence, then beware.

In fact, the drop in atmospheric pressure at high altitudes is so acute that even human travellers on foot must stop at different levels to let their biology acclimatize to the lower pressure and different oxygen levels. This, obviously, will be the same for those visitors from parallel Earths or the past or future. Visitors from other planets who require environment suits against the Earth's atmosphere in general should have no problem, as they will be protected anyway. Those who would otherwise be able to withstand the regular surface conditions on Earth should keep pressure suits and portable atmospheric supplies available for use in those areas where the pressure and atmospheric content levels vary.

How much actual warfare you engage in during your operations on Earth will depend both on your motivations, and the reaction you receive from the natives. However much fighting you end up doing, the golden rule to remember is that the purpose of warfare is
victory
, not endurance or scale.

When warfare was limited only to units of ground forces on land, and ships at sea, pitched battles of massed units were perfectly normal, as these armies were what decided the rulership of Earth's nations. With the development of aircraft, missiles and drones, this has become less the case, at least for those nations who have such forces. Since you will be coming with superior technology, you should not actually need – unless you're doing it wrong – to engage the enemy in massed naval or infantry battles. Swarms of troops having it out on the open field, while still an attractive idea to certain cloned armies who have no need to concern themselves about casualties, are basically a waste of time, and a sign of bad strategic planning on the part of any invader from orbit.

There will always be the need for smaller-scale engagements, such as commando raids to capture or destroy enemy facilities, but when any army in the field can be eliminated from the air or from space, by bombs, missiles, meteors, energy weapons, or whatever, then there's really no need to land an army of your own to meet the enemy's army. That said, if you have a particular cultural or religious requirement to meet your enemies face to face, then that is your privilege and you can feel free to do so. Naval actions should be similarly unnecessary, of course.

It will be a different matter for those of you arriving from a parallel Earth. In this instance you should simply follow your world's or nation's standard military doctrine for invading a neighbouring society.

Invaders from more advanced time zones, or who have come through teleportation, wormholes, or other non-starship means, will fall somewhere in the middle. It may well be necessary for you to engage terrestrial armies in the field, but your superior technology should enable victory. The rules to remember here are that, aside from having done your research, you should always be deceptive, and warfare has traditionally depended on deception and concealment for victory. Also, your logistics will be of far more importance than those of the native population, or of invaders from orbit. Invaders from orbit can always drop something on the enemy, but you who are confined to the planetary atmosphere cannot, so you
must
be sure that you can bring through enough materiel and reinforcements from your home before you engage the enemy.

Present-day Earth is a theatre of asymmetric warfare, rather than classical land or sea warfare. This means that the opposing forces are not equal in doctrine or strategy – one side may rely on open strategic bombing and armoured units, while the other concentrates on stealth and infiltration, for example. As a visitor to the planet, it is highly unlikely that you will just happen to be equal in mindset and ability to the human forces opposing you. You will be engaging in asymmetric warfare of one kind or another, and must know in advance which type of warfare you will conduct.

Spaceborne invaders should project their power from above to eliminate enemies at long range, while invaders able to roll massed troops and equipment through a wormhole or dimensional rift can engage in a traditional invasion, and those with little superior technology or backup from home can use stealth and infiltration techniques.

In general, however, all would-be conquerors of the Earth should find themselves in a position of conducting more quick hit-and-run raids to seize or destroy objectives, and policing actions to retain control of captured and pacified areas.

As with any other military activity, camouflage is an important part of preparing for and carrying out your invasion. It is always best in military actions to be covert, deceptive, and not seen, unless you have some honour code about being open, or an animal instinct driving your species to be obvious in order to issue challenges.

Assuming neither of those is the case, you should ensure that your forces – both vehicles and warriors – in combat are appropriately camouflaged.

This is easier for any starships you have; even without the need for energy-based cloaking devices, the sheer size of space as compared to any starship makes the ship no more than a speck at most distances, so simply preventing energy leakage from it and painting the hull black is a good way to start. On Earth, and as the individuals or materiel to be camouflaged shrinks in size, things begin to get more difficult. If you have energy-based invisibility shields of any kind, you should of course use them. If not, then there are things you can do instead. Take tips from Earth militaries, by using camouflage paint, and stealth technology.

Vehicles should be painted to blend in with the background environments in which they will be used. If possible, antimagnetic paint should be used, and any heat exhausts or power systems disguised with heat-absorbent baffles to prevent tracking by heat-seeking sensors. Radar-diffusing paints should also be handy.

As for your troops, they should also be given a means of camouflage. Personal invisibility cloaks are best, but have problematic side effects; if your eyes work the same way as human eyes, they need light to impact the retinas in order to be translated into visual information by the brain. Anything that prevents light from reaching you – such as invisibility – will also prevent this, and so render you blind. Therefore, if you have such cloaks, you will need to equip your forces using them with some other form of sensor to replace their vision.

Otherwise, either their clothing or their outer surfaces (if they do not wear clothing) should be of a drab colour to suit the background of the environment in the combat area, as per human protocols.

Once you have landed your forces on Earth, whether by means of descent from orbit, or arrival through time or across the barriers between dimensions, you will now be faced with the practicalities of mounting your campaign on the Earth's surface.