What is NATO and why are the world’s most powerful leaders suddenly so worried about it?

It’s a political and military alliance between North America and Europe that was born out of World War 2 and signed into effect in 1949. Its main aim back then?

To push back against any future aggression from the Soviet Union. This became particularly important in 1955 when the Soviet Union and seven other European countries signed the Warsaw Pact.

Communism was spreading across Eastern and Central Europe – and this pact promised military support for Soviet satellite states. There were 12 original NATO member countries – today there are 28.

Seven of those are former Warsaw Pact countries. Each member of NATO has an equal say in discussions and decisions. One of the most important principles of the NATO Treaty is Article 5.

What is NATO?

It states that an attack on one country is, in theory, an attack against all members. In theory all troops and equipment in each nation is available for NATO to use. That means there are 3.5 million active personnel and another 3.7 million in reserve.

So if it really came down to it, 7.3 million ‘NATO forces’ could be mobilized. But Article 5 has been invoked only once in its nearly 70-year history – the day after 9/11. It led to NATO action in Afghanistan.

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Collectively, NATO member states account for most of the globe’s military spending – just under one trillion dollars. In 2006 all 28 member states agreed to spend 2% of their GDP for the alliance’s defense spending. But in fact, in reality, that target is rarely met.

In 2015 the median spend was just 1.18%. The United States spent a whopping 3.7%. That means that America accounted for 70% of the alliance’s total defense spending and it is only one of 5 countries to spend more than 2%.

NATO admits the funding imbalance has been an issue since the start of the alliance, and that it does cause friction. During his Presidential election campaign, Donald Trump threatened to pull out of the treaty, calling it ‘obsolete.’

He also said the U.S. would only help countries that paid their fair share. A major test of Trump’s tough stance could come in 2017 when US troops are due to be deployed in Eastern Europe under Washington’s European Reassurance Initiative.

The U.S. had gradually withdrawn its military presence from Europe since the fall of the Soviet Union… But that all changed in 2014 when Russia seized Crimea and started conducting military operations in eastern Ukraine.

The U.S. responded with a $1 billion emergency response. Next year, that budget is set to triple to $3.4 billion.