Why do Muslims abuse non-Muslims by calling them ‘Kafirs’?

NON-MUSLIMS REFERRED AS ‘KAFIRS’

'Kafir’ means one who rejects.

‘Kafir’ is derived from the word ‘kufr’, which means to conceal or to reject. In Islamic terminology, ‘Kafir’ means one who conceals or rejects the truth of Islam and a person who rejects Islam is in English called a ‘non-Muslim’.

If non-Muslims are hurt - they should accept Islam.

If any non-Muslim considers the word ‘Kafir’ i.e. ‘non-Muslim’ as an abuse, he may choose to accept Islam and then we will stop referring to him as or call him a kafir i.e. a non-Muslim.