Still, the Bolivians were controlling the insurgency more effectively than American communications between La Paz and Washington suggested. In June and July, Guevara began operating further north in the province of Vallegrande, much of the time in territory that was both more barren and more rugged than the area where he began his operations. He had been forced into the region, which proved less able to support his band and harder to traverse, by the Bolivian Fourth Division, headquartered at Camiri, which had maintained continuous pressure on him farther south, around Nancahuazu.
Unquestionably, the Bolivian forces benefited from many kinds of U.S. assistance as they faced Guevara's guerrillas. Besides invaluable help with field intelligence, they received substantial amounts of new equipment. Although it fell well below the initial hopes of the Bolivian high command, it included automatic weapons to nine companies besides the Second Rangers, plus field rations, communications gear, and several helicopters. Some of this arrived a year or two before the insurgency broke out in anticipation of trouble, some was on order for future years but delivered early, and some was provided specifically to meet the emergency. 6 Certain units that received U.S. supplies were sent to the guerrilla zone to reinforce the troops already there, although by far the greater number stayed in the cities and the mining area. Finally, many of Bolivia's officers had undergone counterinsurgency training at Fort Gulick in the Panama Canal Zone or in courses given by Americans in Bolivia. (One of the less successful graduates of the latter was the major captured leading the ill-fated ambush on March 23 that opened the fight with Guevara.)
The Bolivians thus had begun to create real problems for the guerrillas, although they received little applause from their allies. By May, the army's new recruits had been trained and had begun to get field experience, and while on the whole Guevara did not give the Bolivian Army much better reviews than the Americans did, he noted some changes. "The army has improved its technique," he reported even as early as the end of April; "they surprised us at Taperillas and they were not demoralized at El Meson." The following month, however, the army slid in his estimation. It "goes on without being organized," he said, "and its technique does not improve substantially." In June, he continued to be unimpressed with Bolivian military capability but noted its intelligence-gathering activities. "The army continues to be nothing militarily," he wrote, "but it works on the peasants in a way that must not be underestimated, because it transforms all the members of the community into informers, whether by fear or by lying to them about our objectives." By the end of July, the month that began with the Samaipata raid, he recorded that "the army keeps on without making head or tail of the situation, but there are units which seem to be more aggressive."