Diplomacy is the art and practice of conducting negotiations between representatives of states. It usually refers to international diplomacy, the conduct of international relations through the intercession of professional diplomats with regard to a full range of topical issues. International treaties are usually negotiated by diplomats prior to endorsement by national politicians. David Stevenson reports that by 1900 the term "diplomats" also covered diplomatic services, consular services and foreign ministry officials.
International mostly means something (a company, language, or organization) involving more than a single country. The term international as a word means involvement of, interaction between or encompassing more than one nation, or generally beyond national boundaries. For example, international law, which is applied by more than one country and usually everywhere on Earth, and international language which is a language spoken by residents of more than one country.
Security is freedom from, or resilience against, potential harm (or other unwanted coercive change) from external forces. Beneficiaries (technically referents) of security may be persons and social groups, objects and institutions, ecosystems, and any other entity or phenomenon vulnerable to unwanted change by its environment.