Syria - how to destroy a combine harvester

Nice vide from the liveleak showing Syrian rebels blowing up a combine harvester with TOW.
video

Syria, systematic attacks from the rebells/ISIS against the infrastructure of the country -- planned migrant crisis

By watching the news around the net I see many videos about rebells  attacking Sysrian army tanks protecting electrical substations and power plants .
There was a news about the US forces bombed a substation few weeks ago.
Data:
Two F16 aircrafts belonging to the so-called US-led coalition violated the Syrian airspace on Saturday, targeting the infrastructure and destroying two power plants in al-Rudwaniya area to the east of Aleppo city, a military source said.

https://www.youtube.com/watch?v=JxMYeU9G314

Pillons around the tank.
https://www.youtube.com/watch?v=ita8aJwQdbc

Another tank , there is a pylon  in the background, and electrical cables in the air , showing another hi volt line.Seems like the tanks is close to a high voltage substation.


http://www.liveleak.com/view?i=060_1445093905

Another video,in this case the rebells or ISIS attack one tank in the front of a electrical substation.


I don't know what is the motivation of the rebels/USA, but the Syrian military putting efforts to protect the country infrstructure.