WASHINGTON (AP) — The United States has long relied on its borders and superior military might to protect against and deter foreign aggressors. But a lack of boundaries and any rulebook in cyberspace has increased the threat and leveled the playing field today.

It's unclear how President Donald Trump, who has emphasized an "America First" approach to domestic issues, will respond to cyberspace threats, which transcend traditional borders and make it easier and cheaper than ever for foreigners to attack the U.S. Whatever the approach, it will set the tone and precedent for global policies durin...