People INSIDE a defensive position who have the aim of keeping the people OUTSIDE the position OUTSIDE for as long as possible.
The position was likely a fort or castle with high walls and water-filled moat.
The position was likely a 'star' fort based on geometric shapes guaranteed to enfilade an enemy attack from any angle.
The position was likely a trench for both sides. Additionally a dugout 30'+ underground with many home comforts if you were a German. If you were a Tommy then it was a pair of socks and a packet of backy... if you were lucky.
The position was likely a small hole in the ground/pile of rubble OR a massively fortified concrete beast that fifty German paras wiped the floor with in fifteen minutes.
Similar to WW2 but without the concrete fortifications.
For the Americans this was a firebase. An encampment surrounded by defoliated and cleared jungle, razor wire, claymore mines, machine gun positions and stuffed with as many 155mm and 105mm artillery pieces as they could crowbar in. The Vietnamese has a cozy tunnel complex hidden UNDER the firebase.
For the British, very similar to Vietnam, but with significantly less defensive firepower - like ten rounds of 7.62's worth - and significantly less Vietnamese and 'boom boom' - of both kinds.
A water-filled trench in a bog, or a bullet-riddled sheep shed. Somebody's house if you were an Argentinean.
Either a pile of sandbags in the middle of nowhere or a five star hotel even further from the action - like in another country.
Also a type of Land Rover.
See Defender AL1