This is a very significant question. Why do we worship shiva with the symbol of creation when we know shiva as the God of destruction?
Firstly, shiva is not the God of destruction because there can be no desrtuction. We know through science that energy can neither be created nor destroyed. It only changes form. Thus Shiva is not the God of destruction but the God of transformation.
Now, when does creation happen? When the previous form dissolves a new one is created. Thus creation and destruction are really two sides of the same coin. Two parts of one process. And shiva is standing in the middle of this two processes.
The famous nataraja idol of shiva depicts exactly that. On one side of it is the dissolution aspect of shiva and on another is the creation aspect. Thus only that which is present at the desolution will be the one present at the time of creation.
Nataraja image at CERN.
Now think of the role of electricity in the creation of water molecule from 2 hydrogen and one oxygen atom. We know electricity doesn’t participate in any way this chemical reaction but it’s role is extremely vital and there can be no process without electricity. Just the presence of electricity does the job.
Understand Shiva’s role in the process of creation and dissolution in the same way. Shiva is what a catalyst is in a chemical reaction. He is simply present in the process, and this presence makes everything possible.