WASHINGTON, D.C.: After months of threats and dwindling hopes the two sides would pull back from the brink of all-out trade war, steep US tariffs on tens of billions in Chinese goods are due to take effect at midnight Thursday.

China already has announced it will respond in kind on the same schedule as the United States while President Donald Trump has countered with a threat to double down by progressively ratcheting US penalties up to a total of $450 billion in goods -- which would represent the lion's share of all of China's exports to the United States.