100 peso bill.

...Roca's approach to dealing with the Indian communities of the Pampas, however, was completely different from Alsina's, who had ordered the construction of a ditch and a defensive line of small fortresses across the Province of Buenos Aires. Roca saw no way to end native attacks (malones) but by putting under effective government control all land up to the Rio Negro in a campaign that would "extinguish, subdue or expel" the indians who inhabited there. This land conquest would also strengthen Argentina's strategic position against Chile.

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