Learning From the Invisible World

We can learn a lot from the invisible world around us. The naked eye can only see so much but once you go to a microscope you begin appreciating the millions of tiny organisms that have the ability to kill us and which have for millions of years.
I want to tell the story of a very famous nasty microorganism; Mycobacterium tuberculosis. The organism is spread from person to person through infected aerosol droplets. One droplet may contain only a few of these bugs.
Once inhaled the bacterium are transported to the lung where they are released from the droplet. But conditions in the lung are not favourable for this bacterium for immidietly it is attacked and ingested by macrophages ( a white blood cell). Now the body may think that it is over. That the macrophage whose main work is to destroy microorganisms has done its job. Think again.
The macrophage then moves to the nearest lymph node. But inside it the bacterium is able to sabotage the main mechanism of its destruction (digestion by lysosomes) and thus this bacteria continues dividing inside the macrophage until it destroys it. The new bacteria invade other macrophages and continue the process of multiplication inside the macrophage and its eventual destruction.
Once the number of bacteria reach a certain level they spill over into the blood stream and cause a bacteremia. The body responds with vehemence using the T-cells (the same ones destroyed by the H.I.V. virus but that is another story) and most of the bacteria are destroyed.
The few remaining survivors travel to a well oxygenated portion of the lungs e.g. the apical lobe and here they wall themselves off and lay low. They lay low and wait. One day when there will be a physical injury to the body e.g. trauma, immunodeficiency e.t.c. these bacteria come alive again and now proceed to wreak the greatest havoc possible on the lungs. It is this stage where you have the coughs, the bloody sputum, granulomas in various body organs e.t.c.
So, compare this to how enemies may want to invade a country. First a few of them arrive with genuine refugees or emigrants and set camp in the country. At the camp they recruit and recruit until their numbers are more than the security apparatus can handle and they spill over into the country and set up bases countrywide.
The government then responds with vehemence and sets up elite units and such. This causes the imprisonment and extrajudicial killings of many of them. The few that survive go underground and lie low. Here they wait. They wait until a day when things go wrong with the country e.g. coups, election violence, riots, popular uprisings e.t.c
They then come out from hiding and ingratiate themselves into the people and consequently into positions of power from where they can control everything without the need for hiding!