Infiltration is happening.
Dictionary
ech·o cham·ber
/ˈekō ˌCHāmbər/
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noun
noun: echo chamber; plural noun: echo chambers
1.
an enclosed space where sound reverberates.
"purpose-built echo chambers allow the addition of natural-sounding reverberation to the recordings"
2.
an environment in which a person encounters only beliefs or opinions that coincide with their own, so that their existing views are reinforced and alternative ideas are not considered.
"people are living in partisan and ideological echo chambers"