Preemptive strike at lunar surface is not even a scientific feasibility at the present R and D stage. Whole of the humanity shall have to work day and night for that capability cutting across political walls. 

In that scenario combined earth power has to strike their base to save their genome but that is a very serious scenario. 

They have the nuclear capability but nuclear onslaught start on a full scale war. 

India should at the very start should think of growing mega farms under covered scenarios. Tactical warfare includes destroying the fields and to save the fields is first counter strategy or it may think to develop lazer guided lazer beams to strike down flying objects in a synchronized way. 

There is a plausible way of a coordinate onslaught by them for that humanity has to unite as its a highly complex war fare. 

Probably you could have never even visualized such a day as it happened to be this evening. Any way what you have already read now its a stark reality for the scientific world. 

They seem to be humanoid (humane like ) having high cerebral powers but aesthetically it may not be a sensible happenings in the universe.