I don't know why you went on to vent. I just said the Romans used the Phalanx early on because they employed a lot from the Greeks and/or Etruscans to build themselves, which they did. Whether in military, arts or whatever.
From the founding of their city-state until the close of the 2nd century BC, the Romans found the Greek-style phalanx suitable for fighting in the plains of Latium. The basic weapon for this formation was a thrusting spear called the hasta; from this the heavy infantry derived its name, hastati, retaining it even after Rome abandoned the phalanx for the more flexible legion.
I found this video about this subject :