Once upon a time planes were only a minor part of world transportation. No longer:
A large and growing share of international trade is carried on airplanes. Air cargo is many times more expensive than maritime transport but arrives in destination markets much faster. … We estimate that each day in transit is equivalent to [a tax] of 0.6 to 2.3 percent and that the most time-sensitive trade flows are those involving parts and components trade. …
Ocean-borne cargo leaving European ports takes an average of 20 days to reach US ports and 30 days to reach Japan. Air borne cargo requires only a day or less to most destinations. … In 2005, goods imported into the US faced per kilogram charges for air freight that were, on average, 6.5 times higher than ocean freight charges. … Excluding Canada and Mexico, 36 percent of US imports by value and 58 percent of US exports by value were airborne in 2000. … In 2004, air cargo as a share of export value was 29 percent for the UK, 42 percent for Ireland, and 51 percent for Singapore; 22 percent of Argentine and 32 percent of Brazilian imports were airborne. … From 1965-2004, worldwide use of air cargo grew 2.6 times faster than use of ocean cargo. (more)
But ships are so much more romantic.
Analogy with other OB posts with "era" in the title led me to expect another part to the post in which it is asserted that our civilization's reliance on planes is unsustainable :)