Commercial Property Tenant

Hi, I am currently leasing a commercial property and running business as liquor store. I had an incident where someone hit the fire hydrant next to the building with car, pouring massive amount of water into the roof and eventually collapsed. The person who hit the fire hydrant does have insurance but coverage is very minimal so he is out of the picture at this moment.
I have insurance that covers all the contents, business loss and Commercial Liability that contains general aggregate, medical payment, fire legal, and so forth. I've contacted them and had them remove all the products and inventoried. The landlord does NOT have property insurance, so roof and electrical system was fixed by the landlord and things were going smooth until I received a letter from landlord's attorney office. The letter was saying that I, as a tenant is responsible for roof and eletricity under the lease agreement section of 'Maintanence', which states

17. "LESSEE, at its expense and risk, shall maintain all of the interior and other improvements of the Premises in good repair and condition including, but not limited to, all necessary repairs and replacements of the plumbing, electrical wiring, windows, window glass, plate glass, doors, and painting".

I looked at rest of my lease agreement and found 'Damage or Destruction' section which states that

20(a). "If the Premises or the building and other improvements in which the Premises are located are totally or partially damaged or destroyed from a risk covered by the insurance described in Section 18(a), rendering the Premises totally or partially inaccessible or unusable, LESSOR promptly shall repair or restore the Premises or the building and other improvements in which the Premises are located to substantially the same condition as they were in immediately before such damage or destruction."

So who is responsible for cost of repairing the property? Was I suppose to insure the building when I am not the landlord?

Thank you,

Duplicate post. Please post responses in the previous post.