Italian naval tonnage: 242,000
US naval tonnage: 240,000
Source is The Rise and Fall of the Great Powers by Kennedy; table 19.
These figures have been misquoted. Table 19 deals with military and naval personnel and gives figures as follows:
Italy: 216,000 (1880), 284,000 (1890), 255,000 (1900), 322,000 (1910), 345,000 (1914)
United States: 34,000 (1880), 39,000 (1890), 96,000 (1900), 127,000 (1910), 164,000 (1914)
Furthermore, any statistics for US naval tonnage should be taken with an extreme degree of caution given the large number of obsolete vessels in the US inventory. Depending on the exact date of the inventory, which is not given here, such vessels could potentially include the USS Powhatan (wooden paddle frigate, laid down 1847, decommissioned 1886) or USS Passaic (single-turret monitor armed with smoothbore guns, laid down in 1862 and decommissioned 1898).
This does seem to be extraordinarily loosely defined, as a comparison of the ships within this category presents a considerable gulf in capacity:
Andrea Doria: 11,204 tons, 16 knots, 4 x 17in guns, 17.75in belt
USS Puritan: 6,157 tons, 12 knots, 4 x 12in guns, 14in belt
USS Terror: 3,990 tons, 12 knots, 4x 10in guns, 7in belt
It also raises the question of why USS Puritan (launched 1882, completed 1896) and USS Terror (launched 1883, completed 1896) are included on the US side, but the Italians are not given ships like Re Umberto (launched 1888, completed 1893).
The Americans, of course, can (other than a small force in San Francisco Bay) concentrate everything they have in sight of the shipyards their ships were built in, with more coming off the ways in the theater on a regular basis, along with all the coal, shells, and replacement personnel they'd ever need.
'Its indigenous steam coal was located in North Virginia and Pennsylvania ; further from the coast and inferior in quality to Welsh steam coal and on the west coast there was no suitable coal for naval purposes at all. Neither did America possess a significant merchant collier fleet or chain of overseas coaling stations. These shortcomings were came to the fore during the Spanish-American war of 1898 when the USN was forced to purchase Australian coal for its fleet in Manila and
employ British colliers to help deliver it, as well as
help deliver American coal along the Atlantic coast.' (from
here; emphasis added)
Coal wasn't declared contraband in the Spanish-American War: however, if the Italians do choose to put coal on their contraband list, neutral British merchantmen will be prohibited from transporting it.
didn't US and CS ship refuel at sea during the Civil War. I seem to remember the CSS Alabama having several Tender ships listed on the CSN Order of Battle so did the CSS Shenandoah
Not strictly at sea, no:
'The next afternoon I had joined my coal-ship, and we ran in to our anchorage, together, in the little, barren island of Blanquilla, off the coast of Venezuela, where we came to about nightfall. This was one of those little coral islands that skirt the South American coast, not yet fully adapted to the habitation of man… we ran in to this anchorage, which I remembered well from having visited it once in a ship of war of the old service... We lay five days at the little island of Blanquilla, coaling ship, and getting ready for another cruise.'