The paralysis that gripped the US government following the Republican victory in the 2010 Congressional elections meant that the US lost the capacity to cope with the expanding depression precipitated by the burst of the housing bubble in 2008. Legislative paralysis deepened the social fissures exemplified with the Tea Party movement. In 2015, the border states of Arizona, Texas and a small portion of Southern California formed a successionist union over the issue of immigration which they blamed for the economic decline of the nation. This action prompted a number of like-minded groups to form across the country and a low level anti-government insurgency emerged.
The US military, initially attempting to rebuild itself after Afghanistan and Iraq, was tasked to combat these insurgencies while that the same time coping with equipment gaps caused by the bankruptcy of some its key systems suppliers, and a bankrupt treasury unable to sustain the required defence budgets. State of the art weapons and equipment found themselves unservicable because spares could no longer be had for key components and fuel costs became prohibitive. The ability to perform basic strategic defence tasks such as airspace monitoring through NORAD became a struggle. By 2027, nearly impossible. The previously well oiled NORAD and US North America Command defence machine was sputtered and creaked and intermitent gaps appeared the continent's radar coverage. Canada was largely left to its own defence.
Internal discord in the US interrupted production and deliveries of F35 fighter aircraft to the Canadian Forces in the late 20-teens. Suppliers of key systems folded and new ones were hard to find. Quality control fell, and the few aircraft that were delivered by the early 2020s suffered critical systems failures. Landing gear failed, avionics shorted. An engine exploded. Canada found itself forced to rely on its creaking obsolete 40 year old CF18s to meet state of the art Russian aircraft, and beg, borrow and steal for new or loaner fighters from European and other allied countries who were dealing with their own economic and security issues. Especially other F35 users who put all their cards in that aircraft. In fact, a tremendous gap appeared in the tactical air power of friendly nations who had signed on to the F35 project. Australia, reliant on a mixed fleet of Super Hornets and Lightnings IIs had enough experience with its F18Es to keep them going.
At the same time, global oil depletion due to the peak oil phenomena was growing increasingly acute. In 2026, summer ice in the Arctic was non-existent. Large tracts of ocean were open to oil exploration and, taking advantage of a severely weakened West and acting on its own need for energy, Russia launched an aggressive exploration program. It simply refused to address international criticisms. Russian drill ships foraged in international waters, right up to the territorial waters of its Arctic neighbours. Armed long range SU-35 interceptors began flying aggressive tactical sweeps near their airspaces as posturing support for the drill ships. These would sometimes "accidently" drift into North American or European airspace to probe the veracity of allied air defences. Many times these probes were only noticed when observers on the ground spotted the Russian aircraft. The crisis of 2027 emerged that March when pairs of Russian fighters broke the sound barrier over Yellowknife and Anchorage on the same day, announcing their presence to civilian air traffic controllers on a completely unopposed penetration. At that point, discussion over Arctic sovereignty and resource access became moot.