why has Russia waged war against Ukraine?

1. Ukraine has become the bone of contention between Washington and Moscow.
2.  Russia wants the West to keep Ukraine and other former Soviet nations out of NATO, halt weapons deployments near Russian borders and roll back forces from Eastern Europe.
   
   
   
3.  Ukraine wants to join the NATO which has not gone well with Russia. Russia thinks if Ukraine is allowed to join NATO, the group would move closer to Russia's borders.
4.  If Ukraine joins NATO, it is eligible to get support from the group's members in case of external attacks.
5.  So, Russia believes Ukraine could attempt to take back Crimea if it joins NATO. Putin too expressed his concerns in this regard recetly.
6.  Hence, Russia demands West to stay out of Ukraine as Putin wants to restore Moscow's influence throughout the post-Soviet space.
7.  Moreover, after the collapse of Soviet Union, Russia lost control of 14 former republics including Ukraine.
8. Putin considers this as tragic as both countries shared a single "historic and spiritual space".
9.  The Russian President demands guarantees from the West and Ukraine that it will not join and that Ukraine demilitarise and become a neutral state.