▁revolution ▁in ▁modern ▁war fare , ▁and ▁the ▁use ▁of ▁bar bed ▁wire ▁on ▁the ▁battle field ▁was ▁one ▁of ▁the ▁many ▁techn ologies ▁re lied ▁upon ▁to ▁ham per ▁the ▁enemy ' s ▁attack . ▁U sed ▁by ▁American ▁cattle ▁ran ch ers ▁since ▁the ▁ 1 8 7 0 s , ▁bar bed ▁wire ▁was ▁adapted ▁on ▁the ▁Western ▁Front ▁to ▁serve ▁a ▁more ▁gru esome ▁purpose ▁than ▁containing ▁liv est ock . ▁Trans formed ▁into ▁a ▁weapon ▁of ▁war , ▁it ▁was ▁sh aped ▁to ▁create ▁dead ly ▁obst acles ▁in ▁the ▁path ▁of ▁assault ing ▁enemy ▁troops . ▁Me ant ▁to ▁trap , ▁ma im , ▁and ▁make ▁easy ▁targets ▁of ▁the ▁oppon ent , ▁they ▁r anged ▁from ▁a ▁single ▁str and ▁of ▁wire ▁arranged ▁to ▁trip ▁men ▁in ▁the ▁dark , ▁to ▁a ▁ 1 5 0 - met re - long ▁construction ▁ ▁and ▁ ▁tall ▁By ▁spring ▁of ▁ 1 9 1 5 , ▁bar bed ▁wire ▁ent ang lement s ▁were ▁an ▁un av oid able ▁element ▁in ▁tren ch ▁war fare , ▁and ▁pos ed ▁a ▁serious ▁threat ▁to ▁all ▁men ▁going ▁' over ▁the ▁top '. ▁ ▁The ▁call ▁of ▁duty ▁The ▁integration ▁of ▁bar bed ▁wire ▁as ▁an ▁instrument ▁of ▁war ▁required ▁the ▁formation ▁of ▁tact ical ▁teams , ▁or ▁w iring ▁parties . ▁Bar bed ▁wire ▁def ences ▁needed ▁to ▁be ▁maintained ▁frequently , ▁as ▁sh rap nel ▁often ▁cut ▁the ▁wire , ▁or ▁the ▁enemy ▁had ▁sab ot aged