Not to mention a sudden curtailment of electricity - no light, heat, water, elevators, gasoline, trains - think of NYC, Boston, Filthydelphia, Detroit, Chicago. In the heat of summer, naturally. If only the parasitic urbanite commie leftists [the takers] knew how they are known and detested throughout the rural and exurbanite areas - the wealth creators, they would live in existential angst.
True. But a curtailment of electricity will be immediately percieved as an act of terror and will be rapidly set to rights by all means necessary with the full support of the majority of the populance. An agricultural strike has several points to recommend it:
It is non-destructive, which will make it difficult for the propaganda organs to label it as "terrorism."
It is passive, which will make it difficult to defend against or curtail, and will also help belie the "terror" label.
It uses their own methods against them, which at least for a time will make it more difficult to denounce.
It can be concealed for a time behind a natural event (drought or flood) or a man-made event (financial turmoil, civil unrest).
It cannot be easily rectified. If there are no crops to harvest and no herds to slaughter it will be a minimum of one year before food becomes available again in any quantity. The hordes will exhaust all available reserves long before then.