Are your tactics driven by strategies all the time?

A Chinese general called Sun Tzu famously said, “Strategy without tactics is the slowest route to victory, but tactics without strategy is the noise before defeat.”

Strategy sets the word "What for"? while on the other hand, tactics tell us how we are suppose to reach the objective, in my opinion tactics are driven by strategies.

to achieve a strategy you need a tool which is tactic to achieve it 

Yes, they are.

Strategies guide us to formulate and implement tactics. Tactics cann't stand alone or formulated separately from strategies