Moos_tachu had enough sense to not lay down a wall of text. I do not :music_whistling:
A Flight Control System (FCS) does so much more than just "You only get 4° AOA". A limiter and a scheduler are part of the system, but it does so much more.
N.B. The following is pretty general, but the only aircraft I truly understand is the Hornet, so I'll draw my examples from it. It's FCS laws are a bit squiffy (like everything Navy), but the principle is the same.
Fly-by-wire, at its heart, disconnects the control stick from the control surfaces. Control stick inputs are run through the mission computer (MC1, assuming we haven't failed anything). The mission computer takes a holistic look at the aircraft -airspeed, altitude, mode selector, gear position, flap switch, Mach No., loading, AoA, pointing vector, INS gyros, fuel load, C of G, stick deflection and hundred other things- and then proceeds to interpret the pilot's inputs, and make them reality.
In the most basic case, the pilot has centred the stick. In the Hornet (other A/C are a bit different), MC1 takes this as an instruction to "maintain 1G". To do this, it makes dozens of little measurements and adjustments every second to all the flight control surfaces.
If it feels a little reduction in G, it checks the stick position. If I haven't commanded nose down, it then checks all the little factors (mainly airspeed) and uses that to schedule a specific (and very small) Both Stabilators Up command, which brings us back to 1G.
If it registers a little left roll on the laser gyro, it checks the stick. If I haven't commanded a little left roll, it checks all the sensors, and then schedules a specific combo of Right Aileron, Left Aileron, Left Fin, Right Fin, Left Differential TEF, Right Differential TEF, Left Differential LEF, Right Differential LEF, Left Stabilator, and Right Stabilator to put the wings level. That's a total of ten different control surfaces for the FCS to call on to correct a little roll.
The beauty, and the importance, of a modern FCS is in all those control surfaces it can call upon. In a Cessna, I move the flaps with the flap switch. I move the ailerons with left and right yoke, the elevators with up and down yoke. The rudder pedals are connected solely to the rudder. In a fighter aircraft, all those control surfaces are available to me regardless of input I am commanding, and the FCS uses them to make the plane's behaviour a perfect representation of what I want.
Let's try a more complicated example. I hear "TwoBreakRight!" over the radio, so I mash the stick right and push for MAX AB. The FCS notes my request for maximum right roll, looks at the sensors, and then moves all 10 control surfaces. What results is pure longitudinal axis roll. The FCS uses the control surfaces to cancel the adverse yaw, and to max out roll rate (the Hornet can roll way, way too fast if you ask it to). When I get to my 87°ish, I haul the stick from full right to full back. The FCS sees this, and cancels the roll, again using all the control surfaces to prevent adverse yaw. It then pushes the stabilators up, and we start to pitch in a circle. When we hit +7.5Gs, the FCS notes the limit, and stops commanding more Stabilator up. While this is happening, the engines have kicked into Min AB, and the igniters are firing. When both engines light into AB (2 seconds from MIL), the FCS opens the gate, and the ABs crank out to MAX (with the nozzles moving appropriately). It also plays with the other controls to keep the turn coordinated. Now that I'm established in a max-rate turn, speed begins to come off. As I bleed speed, the FCS calls on more Stab Up (the Hornet has a lot of stab). With more Stabilator comes a higher angle of attack, so the FCS begins to drop collective LEF and TEF (including the ailerons, which function like flaps here). This will continue until we've got max maneuvering collective controls. Above 22° AoA, the stick force will kick in, as the FCS politely asks if I actually want to be doing what I'm doing. With 35 pounds of force, I can continue to command full aft stick. At 35° AoA, we'll have maximum lift, and the departure tone will sound. The Hornet can go farther than this (55° AoA steady flight is possible, LEREXs are basically black magic), but we rarely want this. When I release the stick (manoeuvre complete, or I've Gloc'd (again)), the FCS pushes nose down until we get below 22° AoA, at which point it goes hunting for 1G again.
All those little bits and pieces let Fly-By-Wire aircraft pull unbelievable manoeuvres. It also lets a designer build aircraft without having to worry about inherent stability (can use control canards, for example). A well built FCS can make those hundreds of little stabilizing corrections every minute without fatiguing, allowing for these sorts of unconventional layouts.
I feel obliged to delve into all this because the Mirage 2000 is a non-traditional layout (although not inherently unstable). Part of what makes or breaks strange beasts such as the tailless delta Mirage is the FCS logic. Tailless delta aircraft have their strengths (lift!), and their weaknesses (low stab authority). A well designed FCS minimizes the weaknesses, and optimizes the strengths. I do not know enough about the Mirage 2000C's Flight Control System to even come close to passing judgement, but it would be lovely to see it well modelled.