WASHINGTON — The signal wasn’t subtle.

While China practiced amphibious landings in a contested area of the South China Sea this month, the U.S. Navy dispatched two aircraft carriers to the area “to support a free and open Indo-Pacific,” the Navy said in a statement.

It’s unclear how close the American and Chinese warships got to one another. But it was among the more dramatic recent illustrations of how U.S.-China relations have veered into what some experts are calling a new version of the Cold War.

Another inflection point came Tuesday. First, the British government reversed its decision and announced that equipment made by the Chinese tech giant Huawei would be banned from the country’s 5G networks, a blow to one of China’s leading companies.Then, President Donald Trump signed legislation and an executive order to punish China over its actions in Hong Kong, the semiautonomous former British colony where Beijing has implemented a draconian new security law in violation of international agreements.

The U.S. Navy also announced Tuesday that it had conducted one of its periodic “freedom of navigation” operations near the contested Spratly Islands, sending a guided missile destroyer into waters China claims as its own. It was the first such mission since Secretary of State Mike Pompeo declared China’s claims to much of the disputed areas in the South China Sea “completely unlawful” on Monday and accused Beijing of “a campaign of bullying.”

China slapped sanctions Monday on certain U.S. lawmakers and other U.S. officials in retaliation for U.S. measures against senior Chinese officials alleged to be responsible for mass detentions, religious persecution and forced sterilization of Muslim Uighur minorities in China’s Xinjiang province.

Last week, FBI Director Christopher Wray issued a stark warning calling Chinese espionage “the greatest long-term threat to our nation’s information and intellectual property and to our economic vitality.”