Maybe. Won't be difficult though. Inflatable cars, etc can sure
be made to look like tanks etc. The problem is the heat signature
but again i think that can be solved fairly easily? I also remember
that Yugoslavia claims to have fooled NATO into bombing the wrong
targets by Laying polystyrene sheets of some sort on the ground;
that supposedly looked like a road from the air.
Thing is nowadays, these tricks might not work that well
anymore.