There has been a dramatic decline in the size and capability of the UK's armed forces
Despite Britain being one of only four NATO member countries that spend more than 2% of GDP on defence, that figure has been creeping downwards over recent years. Successive governments have sought to remodel the UK's armed forces away from the large-scale standing armies of old toward more elite tactical units befitting the military demands of the 21st Century.
The International Institute for Strategic Studies' annual report of international defence claim that the UK has cut defence spending by 8% in real terms (spending adjusted for inflation) during the current parliament, causing an estimated 20-30% reduction in military combat capabilities.
In layman's terms - the government wants to commit less money to defence, and so the military is getting squeezed.
Some MPs have complained that the reduction in military spending is starting to impair Britain's ability to combat new threats that are emerging. In particular, the increased activity of Russian military ships and aircraft in NATO airspace has raised more than a few questions. Russian planes and submarines have both travelled near or into British territory in the last few days.
Here are the numbers:
The number Navy 'workhorse' ships has been halved: The Royal Navy has seen the number of cruisers, destroyers and frigates - the traditional workhorses of the fleet - fall from 36 in 1996 to 18 as of April 1 last year - 5 destroyers and 13 frigates. Meanwhile the number of submarines has fallen from 15 to 11 and the number of aircraft carriers boasted by the navy has dropped modestly from 5 to 4.
Aircraft carriers that have no aircraft: There are two new aircraft carriers currently being built for the Royal Navy, the HMS Queen Elizabeth and the HMD Prince of Wales, with the former due to enter service in 2017. However, there will be at one major thing missing at launch - aircraft. The planes is is supposed to carry won't be available for three years after that.
The cost per plane has risen to $161.1?million and, at this stage, they are not set to come into service until 2020. That is, the HMS Queen Elizabeth will effectively be a floating hotel for its first three years.
The Air Force doesn't have any maritime patrol aircraft: But the Royal Navy isn't alone in seeing its numbers thinned over the past few years. The Royal Air Force has seen the number of combat fighters at its disposal drop from around 220 in 2006 to 149 last year. The total number of squadrons in the RAF has also been reduced from 47 in 2013 to 44 in 2014.
Furthermore, Britain now has no maritime patrol aircraft after the RAF scrapped its orders for a replacement of the Nimrod aircraft in 2010.
Fighting power has been halved: Retired Air Chief Marshal Sir Michael Graydon and retired Vice Admiral Sir Jeremy Blackham warned in The Spectator of "glaring gaps in our [defence] capabilities". They wrote:
"The House of Commons Defence Committee have suggested that there has been a halving of fighting power since 2010 - and this without considering the serious reductions in the previous decade ... No maritime patrol aircraft, loss of combat power in the Royal Navy, just three squadrons of Tornado ground attack aircraft to conduct the nation's operations, and major manpower weaknesses."
Russian warships have also traversed the English Channel twice over the past few months as the country steps up military exercises as international tensions have risen over its role in the ongoing crisis in Ukraine.
Earlier this week a Russian Tupolev TU-95 bomber, known as Bears, was intercepted by two RAF Typhoon fighters as it flew off the coast of Cornwall. It was the second such interception of Russian aircraft in a month. Over last year as a whole, NATO made 100 interceptions of Russian aircraft.
The incursions are routine - no one seriously believes Russia might take military action against the UK. But the charts show there has been a decline in the amount of equipment available to the armed forces even to monitor Russian military activity in Western Europe.