TCS Research Frontier with Huge Practical and Industrial Impact on our Society
There are many examples of theoretical research that had a big impact on society, e.g., the RSA cryptosystem, the algorithm behind Google search, the algorithmic ideas behind Akamai, etc.
But the thing with basic research is that it's hard to know in advance what's going to be influential, when and how.

One potential candidate could be quantum computing, which has strong ties to both physics and electronics, and could make a huge difference (allowing efficient simulations of quantum systems, breaking RSA, and more). However, it's hard to know when quantum computers will be built (if at all).