Business
Business is the activity of making one's living or making money by producing or buying and selling goods or services. Simply put, it is "any activity or enterprise entered into for profit. It does not mean it is a company, a corporation, partnership, or have any such formal organization, but it can range from a street peddler to General Motors." The term is also often used colloquially (but not by lawyers or public officials) to refer to a company, but this article will not deal with that sense of the word.
Diplomacy
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
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.
International Business
International business consists of trades and transactions at a global level. These include the trade of goods, services, technology, capital and/or knowledge.
Diplomacy
I'd like to think the best bunker buster is a diplomat.
Scott Ritter, in Chris Davis, "Scott Ritter Says Controversial Things About Clinton, Bush, Fox News, the Surge, etc.", Memphis Flyer (May 3, 2008).
Diplomacy
An ambassador is an honest man sent to lie abroad for the good of his country.
Henry Wotton, Written in the album of Christopher Fleckmore (1604).
Business
I believe that leaders and leadership teams working together in a proper design will run the business more effectively than by hierarchical, command-and-control managing. But I can't prove that. And there are no models.
Marvin Bower (1966) The Will to Manage p. 7.