Putin started the war in Crimea to mask the internal issues in Russia???

"Putin started the war in Crimea to mask the internal issues in Russia" - this partially makes sense. It kindled the sense of fair patriotism in people so they could be less distrurbed by actual russian insufficiencies and flaws of the government. But how could we know whether Putin had exactly this intention in mind when he conceived of Crimea's annexation?

-Very good.  Remember that when using "it", the reference to what "it" is must be clear.  In your second sentence it is not clear whether

1. the war kindled patriotism

or

2. the claim that "the war masked internal issues" kindled patriotism.