Largo Caballero's general staff had planned a large offensive in Extramadura, southwest of Madrid, early in 1937. There were several reasons to choose this area instead of New Castile to the west and northwest. The Nationalists in this area were thinly spread, inexperienced, and less well equipped than in the centre. Franco would find it more difficult to bring in reinforcements. Left wing guerillas were operating in Extramadura as well, though their effectiveness was probably overestimated. The arguments against an offensive in Extramadura were the difficulty of achieving surprise after moving the necessary quantity of troops into the area, and the long supply lines from Madrid. Nevertheless, an offensive in Extramadura was likely to be more effective than an offensive in the centre, where the Nationalists could rapidly redeploy their forces, and bring the Condor Legion back from the northern front.
Arguments swiftly proved irrelevant however, as the Soviets vetoed the plan. The communists were as obsessed with the fight for Madrid as Franco was until a short time before. Much communist effort had been invested in Madrid. It was the centrepiece of their propaganda campaign. Also, the Extramadura campaign was originally suggested by General Asensio Torrado, who had earned the wrath of the communists by attempting to reduce their influence, and the communists could not be seen to go along with one of his plans.
This marked the first real dispute between the Republican military and their communist overseers. Some of those who at first welcome communist ideas on discipline started to suspect that they were more interested in extending their own influence than in winning the war. They were dismayed by the complete misrepresentation of events for propaganda purposes and alarmed at the vitriolic campaigns of lies waged against the likes of General Torrado, who had dared criticise the Party's manipulation of military supplies.
Republican commanders soon found they faced a flat out Soviet refusal to commit tank and air support to an Extramadura campaign, while General Miaja in Madrid pointedly refused to obey orders to transfer formations from his command to the south. Prieto, the new defence minister of Juan Negrin, still believed in close cooperation with the communists. It was not until this sorry episode that he began to change his mind.
The communists chose an alternative to Largo's project, an offensive against Brunete, a village 30km west of Madrid, some distance west of Boadilla del Monte. This was to be the Party's show of strength. All five International Brigades and the communists best known formations were given key roles. Every Republican commander had a Soviet adviser at his elbow. Miaja was in charge, and he could count upon 129 tanks, 43 armoured cars, 217 guns, 50 bombers and 90 fighters - by far the largest concentration of strength yet seen in the war. And yet this force had crucial weaknesses hidden behind the numbers. The Popular Army was not up to the logistical challenge of supplying such a huge force, and the communist commanders were notable by their lack of initiative and excessive caution. This may have been surprising in aggressive 30 year old communist commanders like Lister and Modesto, but their first experience of military command was only in the sierra engagements of last summer. While they were daring and resourceful at battalion level, they now commanded forces up to 30 battalions in size and had to cope with unfamiliar staff procedures. They were, simply, overwhelmed by the challenge of commanding a force of this size, and events were to prove that they were not up to the task. But if the new communist leaders of the Popular Army were intimidated by their new responsibilities or conscious of their limitations, they did not show it. As with the International Brigades at Jarama, ignorance and poor tactics were concealed behind bluff confidence, harsh discipline, and propaganda.
