NATO: How Finland will fight in a war with Russia after Ukraine invasion

Finland, along with Sweden, has officially been accepted into the NATO alliance. The small nordic country of just 5.5 million people, which shares an 800-mile border with Russia has reversed decades of neutrality to join the ranks of NATO in a massive blow to Vladimir Putin. So, what will Finland bring to the alliance? In this documentary the Sun's Max Molyneux travels to Finland to meet members of their 900,000 strong reservist army, attend a live-fire military exercise with young Finnish conscripts and tour one of the countries largest public nuclear bomb shelters. Find out Finland has spent decades preparing their country for war and how this readiness will strengthen NATO's northern flank.