Battle for Santa Monica
Santa Monica is a district within Los Angeles, near the pacific ocean and close to Venice beach. During the film the area is amongst the first district to be directly assult by the unknown alien invasion force which breached the atmosphere and landed just out to sea. Within minutes the region is tranformed into a giantic, desperate struggle over the local land.
The area was partly evacuated before the invasion due to the threat of isunamis from the massive meteors falling to earth. Despite this many people remained in the area wanting to watch the huge splashes creaed by the falling meteors, unknowing that they were not meteors and they were under threat from these invaders who landed acrossed the sea front. Coast guard and other services were deployed to the region to no effect as most of the coast guard ships were destroyed by the meteors and the police were entirely overwhelmed within minutes and unable to defend the population.
Military units were deployed to the region with several battalions of mechanised infantry (possibly a stryker or BCT) armed with tanks (M1A1HA Abrams) humvees, cobra gunships, apache gunships. Further reinforcements (marines estimated 1,000 according one of the characters) were airlifted from local military bases by chinooks, hueys, blackhawks and ospreys. Estimated troop strength 1,000 marines, 4,000 soldiers from a BCT, 150 helicopters, 20-30 fighter jets. Against unknown strength of the opposition.
First few hours
Human military forces looked to be in a good shaped throughout the morning, dealing out harsh bombardments to to large amounts of alien forces hoping to breach the US defences. They had control of the skies, with the aliens producing little AA defences against the full weight of the US airforce as it strafed the invaders on the beach and in the city. Together with infantry and armour on the ground, the human forces looked to be in aa good position to hold out despite having lost alot of men and land to the aliens.
On the radio during the film several units can be heard calling for help and airstrikes as the marine forces get briefed at the FOB. But with total control of the skies the US could of turned this invasion into a masscre for the invaders.
Towards the middle of the day, the aliens counterattacked the human forces using hundreds of drone aircraft to attack the American Forces on mass. The human air forces were quickly almost annihilated possibly while they were still on the ground (destroyed helicopters seen at the FOB). Alot more superior weaponry was used such as hover tanks and drones armed with rocket launchers during this counterattack. This could be another reason why the human forces crumbled so easier under the pressure.
Evacuations from Santa Monica
With their air support decimated and their forces in disarray, a general withdrawal order was probably made to save some of the troops stationed in the field. During this point the FOB was probably overrun and burnt, a few EVAC centres remained operational until they were finally overwhelmed or abandoned. LA was considered lost by this stage of the war.