French Declaration Discouraging Cyberattacks

The US was one of the few western countries that declined to sign France's new declaration that discourages the use of cyber attacks, specifically on civilians. It was signed by 51 countries, over 130 companies, and 90 universities and nongovernmental groups. The declaration aims to prevent and decrease meddling in elections and prevent harm to individuals and infrastructure. The US did not provide explicit information as to why it did not sign. 

What are the consequences of the Trump administration failing to sign this declaration? Do you agree or disagree with the decision?