Why was NATO founded?

The precursor to NATO was a purely European affair. The Treaty of Brussels on mutual defense was signed on March 17, 1948, between Belgium, the Netherlands, Luxembourg, France and the United Kingdom. It was mainly intended to counter the perceived threat posed by the Soviet Union –there were jitters after Czechoslovak coup in which the Communists overthrew a democratically elected government.

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The Korean War also stoked fears that the Russians might push through Europe to the Atlantic Coast. Talks on an alliance that spanned the Atlantic began in 1948 and the North Atlantic Treaty was was signed by US President Harry S. Truman on April 4, 1949. As well as the US and the original 5 members, the resulting North Atlantic Treaty Organization included Canada, Portugal, Italy, Denmark and Iceland.

The effective aim of NATO is to keep its members safe by deterring attack, and to bind the US to this collective defense. There are now 29 members.

What part did Germany play?

The British, French and US occupied zones of Germany became the state of West Germany in 1949. Russia proposed the withdrawal of all militaries from Germany, and its reunification as a neutral state. This is what happened with allied-occupied Austria – spilt in a similar way to Germany but where all four zones combined in 1955 to form a neutral state.

Russia even proposed joining NATO itself, thinking that would provide an insurance against any resurgent German military threat.

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That was rejected by the Western allies and West Germany joined NATO in 1955. The rearming of West Germany within NATO brought about the formation of the Warsaw Pact between Russia and its East European satellites.

An Iron Curtain descended in Europe until the pact unraveled with the fall of the Berlin Wall. In the next 20 years, several Warsaw Pact countries that were outside the Soviet Union, including East Germany, each became part of NATO.

How does the alliance work?

Under Article 5 of the treaty, an armed attack from outside the alliance on any one NATO state would be considered as an attack against all NATO allies. The alliance members are sworn to help the party being attacked.

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Unlike the Treaty of Brussels, assistance to another NATO ally would not necessarily have to be by military means, but it is still assumed that any response would involve use of force. To make joint action easier, national militaries seek to use the same procedures and equipment, and carry out joint exercises.

NATO has only invoked Article 5 of the Washington Treaty once, after the September 11 terrorist attacks on the US.

The treaty was later clarified to include members' territories, vessels, forces or aircraft above the Tropic of Cancer. For this reason, the alliance was not involved in the 1982 Falklands War between Britain and Argentina.

Who runs things?

Decisions are made by the North Atlantic Council, which has permanent representatives from each of the member countries. Its membership can also be composed of ministers of state or even heads of government.

Meetings are chaired by the Secretary General of NATO – the top international civil servant who is in charge of international civilian staff. The Secretary General is chosen by consensus among member states, usually through informal diplomatic channels.

Because the top military officer of NATO, the Supreme Allied Commander Europe (SACEUR), is always an American, the Secretary General has traditionally been a European. The Deputy Supreme Allied Commander in Europe is usually British, although three Germans have also served in the role.

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The North Atlantic Council is advised on military policy by the NATO Military Committee, the chairman of which can come from any country. This is also one of the foremost roles in the alliance.

The alliance is run from NATO headquarters in the Belgian capital Brussels, with the military headquarters of Allied Commmand Operations near Mons, also in Belgium.

How is NATO funded?

There is direct and indirect funding.

Direct funding pays for things that are not the responsibility of any one individual country, such as NATO-wide air defense or command and control apparatus. This is paid for according to a cost share formula based on the Gross National Income of each country and represents a small portion of each country's defense spending.

Indirect funding pays for exercises and military operations. Each country pays the cost itself and the level of commitment is often assessed on the defense spending of each country. In 2006, NATO members agreed to commit two percent of Gross Domestic Product (GDP) to defense spending.

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Most countries have not done this. Outside the US, only Britain, Greece, Estonia and Poland spend above the two-percent guideline.

While the combined non-US members have a greater GDP than the US, America spends more than twice as much as they do on its military. The imbalance increased all the more after the 2001 terror attacks on the US, when Washington hiked up its defense spending.

Has NATO's purpose changed since the Cold War?

With the Cold War effectively won, NATO actually became more militarily active. Indeed, while there were no military operations during the Cold War itself, the years that followed saw NATO operative in a wide ranging geographical area.

NATO supported  a US-led coalition in the First Gulf War. It helped operate a no-fly zone over Bosnia and Herzegovina during the Bosnian war of the early 1990s. NATO also became involved in Kosovo, where an air campaign was carried out against Serbian troops engaged in a crackdown on ethnic Albanians.

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The alliance probably saw its greatest real-life challenge in Afghanistan, in the wake of the September 11 attacks. The alliance is still active in the country with the Operation Resolute Support program to train Afghan forces. While NATO wasn’t involved as an alliance in the invasion of Iraq, it did provide training support there, too.

NATO has also taken part in enforcing a no fly-zone and military action to protect civilians in North Africa. It’s also been involved in anti-piracy operations.

Why are relations with Russia still bad?

After the fall of the Berlin Wall, NATO and the Soviet Union held talks to push for arms controls and things began to look quite rosy, for a while.

The possibility was even floated again that Russia might become a member of NATO. In 1990, while negotiating German reunification with the US, then-Soviet President Mikhail Gorbachev made a direct proposal to join. The US Secretary of State James Baker dismissed the idea as a "dream."

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Despite this, the Russian Federation, as a successor state to the Soviet Union, became a member of the Partnership for Peace program with NATO, signing agreements on cooperation in spheres such as anti-terrorism.

However, relations between NATO and Russia have soured with time. NATO's intervention against Serbia's crackdown in in Kosovo caused anger in Russia, a traditional ally of Serbia. Russia felt NATO was encroaching on its sphere of influence by forming partnerships with states on its borders, such as Georgia and Ukraine.  After Russia's takeover of Crimea in 2014, NATO suspended cooperation with Russia.