Mutual Defense Agreements & Strategic Partnerships: A Look At International Armaments Cooperation

The 20th Century revolutionized warfare as we know it. We saw the two largest wars the world has ever known. War machinery advanced at a rate that had never before been seen. The difference in primary fighter aircraft from 1936 to 1946 was incomprehensible; naturally aspirated pistons were the norm at the beginning of the war, and at the end, the jet age was well underway. 

Besides the obvious differences in machinery and technology, tactics changed radically. But perhaps even more significant to the geopolitical landscape has been how nations have formed alliances and strategic partnerships. 

Mutual Defense Agreements and Strategic Partnerships are every bit as important to national defense and global security strategies as the equipment they use. Let’s examine mutual defense agreements over the decades and their impact on the modern national security landscape. 

A Brief History of Mutual Defense Agreements

How far back do MDAs go? Strategic partnerships are nothing new. In fact, they date back centuries. 

Pre-World War I Alliances

Military coalitions are absolutely nothing new under the sun. There have been military alliances since the Old Testament, where nations with similar goals or similar foes formed military alliances. 

Pre-World War I alliances were a significant factor in the geopolitical landscape of the early 20th century. These alliances, often formed in secret, created a complex web of relationships between major European powers. The Triple Alliance, consisting of Germany, Austria-Hungary, and Italy, was one such alliance that changed the history of the world forever. In fact, it would ultimately usher in ‘The Great War,’ which was thought to be the war to end all wars. Of course, it was not.  

The Triple Alliance was formed in 1882 and was intended to provide mutual support in case of an attack by other major powers. On the other side, the Triple Entente, comprising France, Russia, and Britain, emerged as a counterbalance to the Triple Alliance. These pre-World War I alliances played a huge role in the escalating tensions and, ultimately, the outbreak of the war in 1914. Unfortunately, it did not end with the Treaty of Versailles. In fact, that would be just the beginning. 

Interwar Period Agreements

The interwar period agreements were extremely important for all future MDAs and strategic partnerships and for basically all geopolitical issues. 

The most significant agreement, and one with ramifications that are felt to this day, was the Locarno Treaties. In 1925, the governments of Germany, Belgium, France, Great Britain, and Italy gathered in Locarno, Switzerland, to conclude a significant treaty. The document, written in French, included the diplomatic seals and signatures of representatives such as Gustav Stresemann of Germany, Aristide Briand of France, and Stanley Baldwin of Great Britain.

The Locarno Pact, as it came to be known, was a symbol of peace and cooperation in Europe following the devastation of World War I. The treaty guaranteed Germany's western frontier, with France, Germany, and Belgium pledging to treat the border as inviolable. In addition, Britain and Italy committed to help repel any armed aggression across the frontier.

The Rhineland, a part of western Germany that the Allied Powers had occupied after World War I, was permanently demilitarized, and occupying forces were withdrawn. The agreement came into force only when Germany was admitted to the League of Nations with a seat on the Council in 1926.

Unfortunately, the hopeful new era of peace and cooperation did not last. The economic and political crisis of the 1930s led to the demise of the Locarno Pact. In 1936, Adolf Hitler denounced the treaty and sent German troops back into the Rhineland. The development was an overt sign of aggression and a warning to the nations both involved in World War I and in the Locarno Pact. 

Post-World War II Developments

The post-Locarno world would enter a very dark period from 1939 to 1945, which we don’t need to cover here. Basically, as far as strategic partnerships are concerned, the complete defeat of Germany and Italy in Europe and the ouster of their leadership shifted the focus to the existential threat to world peace, which was Communism. 

NATO and the Warsaw Pact

To be totally frank, almost as soon as the guns went silent in 1945 and the ink was still drying on the Instrument of Surrender, it was clear that the Soviet Union represented an enormous threat to world peace. 

The post-World War II era saw the emergence of two major military alliances: NATO and the Warsaw Pact. NATO, the North Atlantic Treaty Organization, was established in 1949 to counter the perceived threat of Soviet expansionism. It was founded on the principle of collective defense, meaning that an attack on one member would be considered an attack on all. 

On the other hand, the Warsaw Pact was formed in 1955 as a direct response to NATO. It consisted of the Soviet Union and its satellite states in Eastern Europe. The Warsaw Pact served as a military counterbalance to NATO during the Cold War, further solidifying the division of Europe into two opposing blocs.

NATO still persists to this day long after the fall of the Communist Soviet Union and the dissolution of the Warsaw Pact in 1991. 


While NATO and the Warsaw Pact were in action in Europe, representing both sides of the Communist expansion of the Soviet Union, a pair of regional defense alliances were established in Asia to prevent the expansion of Communism across the Pacific Rim. 

This would be the Southeast Asia Treaty Organization or SEATO. Paralleling NATO, SEATO was formed in 1954 (during the Korean War) to prevent its further spread. Of course, it was already making rounds with the Vietnam War looming on the horizon. 

The Central Treaty Organization (CENTO) was another military alliance in the Middle East that prevented the Soviet Union from encroaching on its territory. 

Key Elements of Mutual Defense Agreements

With some historical context provided for the history of agreements and the simple truth that they don’t always work out, let’s take a look at the key elements of mutual defense agreements and military alliances. While the machinery is not the be-all and end-all of strategic partnerships, it’s a very important component. Greenwood Aerospace is your trusted source for Foreign Military Sales program expertise and procurement. 

Defense Commitments

The very backbone of all MDAs is the defense commitments. These are the promises that all parties or nations involved agree to support each other militarily and defend each other for the common good. Here are a few good examples of defense commitments:

Treaty of Lisbon

The Treaty of Lisbon introduced a mutual defense clause that requires member states to aid and assist a member state that is the victim of armed aggression on its territory. In fact, the Treaty of Lisbon also amends a pair of treaties that form the constitutional basis for the European Union (EU). 

Republic of Korea Treaty

This treaty, signed in 1953, states that an armed attack in the Pacific area on either party is dangerous to their peace and safety. The U.S. continues to strongly support this with thousands of military members stationed in South Korea to this day, along with strong Foreign Military Sales alliances with ROK. 

Rio Treaty

The Rio Treaty, signed in 1947, states that an armed attack against any American State is considered an attack against all the American States.

Article 5 of the North Atlantic Treaty

This article guarantees the mutual defense of its members. If a NATO Ally is attacked, each member of the Alliance will provide any assistance they deem necessary.

Mutual Defense Treaty (United States–Philippines)

The Mutual Defense Treaty between the U.S. and the Philippines was part of President Obama's Global Development Initiative, which was designed to strengthen the Philippines' business development and commercial ties with the U.S. 

Collective Defense Clauses

Collective defense clauses are the mechanisms that stipulate that an attack on one ally is an attack on all. I.e., if one nation in NATO is attacked, then it is considered an attack on all of them and the participating nations are obligated to take up arms against the aggressor(s). 

This principle is detailed in Article 5 of the North Atlantic Treaty. 

Strategic Partnerships and Armaments Cooperation

Alright, now we focus on strategic partnerships and armaments cooperations. 

Defining Strategic Partnerships

An important distinction should be made between alliances and strategic partnerships. Alliances are formal agreements between participating nation-states. The most commonly known examples of alliances are NATO, NORAD, and ANZUS. 

Strategic partnerships are less formal relationships between nations. They are often centered on building relationships with other nations. The U.S. does this all the time by sending troops for aid, like assisting in building or repairing infrastructure. Another common activity in strategic partnerships is military-to-military exchanges. For instance, pilots of common airframes will go on an extended partnership with an allied nation to fly with their Air Force. 

Notable Strategic Partnerships

The U.S. is participating in a few noteworthy strategic partnerships presently, although these are always subject to change. Since nations are not bound to partnerships as they are to treaties, they can be closed or opened at will.

The Pacific Partnership Strategy

The U.S. is vested in bolstering the Island Nations in the Pacific Rim. This region has long been recognized for its strategic importance, particularly given the stark realities of Communist Nations actively in the region. 

The Pacific Partnership Strategy aims to strengthen our ties and presence in the Pacific Rim by addressing the key challenges in economic development and regional security. The U.S. aims to foster economic opportunities, enhance connectivity, and support the empowerment and prosperity of Pacific Islanders through targeted initiatives in infrastructure, cybersecurity, and financial linkages.

What’s the Common Ground Between MDAs and FMS?

Bringing this whole thing back around, Mutual Defense Agreements (MDAs) and Foreign Military Sales (FMS) are interconnected elements of a strong global security strategy. While MDAs are formal treaties committing countries to mutual defense and defensive cooperation, FMS meet the demand for advanced military capabilities and armaments. 

After all, what good is a treaty if it has no teeth? 

But it goes beyond that. MDAs and FMS work together to boost and strengthen alliances by economic and political action. This is done by developing and executing long-term defense procurement plans, which create deep military and industrial relationships. 

FMS is also the catalyst that promotes standardization and interoperability of military equipment among Allied forces. The Allies painfully learned this lesson during World Wars I and II; war machinery and armaments that weren’t compatible created logistical nightmares. Since all of the Allies were using different calibers and primary weapons, they could not share excess when other Allies needed them. 

Finally, FMS does provide the practical means of supporting the security guarantees laid out and agreed to in MDAs, reinforcing these collective defense agreements by equipping all member nations to defend not only themselves but also their allies adequately. 

Parting Thoughts

In the grand scheme of the national security framework and international relations in general, MDAs and Strategic Partnerships are the bonds that hold nations together to pursue national security. 

With threats to global security constantly on the horizon, these agreements and partnerships are as important (if not more) than ever. MDAs and Strategic Partnerships help shape the geopolitical landscape by fostering cooperation among nations with shared interests. 

Greenwood Aerospace is your trusted partner in securing FMS contracts, whether you are looking for military service contracts, defense articles, or replacement parts. Whatever your mission dictates, we will source and procure it. Give us a call or start an online quote today!