In doing so, the Allied naval forces engaged in a series of duels with coastal batteries and provided close support to infantry as they fought to gain control of the city.

In response, the Allies renewed their efforts to capture the city, and by June 20 three infantry divisions under General "Lightning Joe" Collins had advanced within a mile of German lines defending Cherbourg.

Under the direction of army spotters, these ships were able to engage point targets up to 2,000 yd (1,800 m) inland, which proved invaluable in providing close support to the assaulting Allied infantry.

When the city fell, the neutralized casemated guns, which the Germans could have turned inland towards advancing Allied troops, were still aimed out to sea.

Once German commanders assessed the Allied assault at Normandy as the primary invasion, they sought to limit the lodgment while they prepared a counter-offensive.

By June 14, the Germans were attempting to deny the Allies use of Cherbourg's major port facility by blocking, mining and demolishing its harbor.

To support the ground assault, Rear Admiral Morton Deyo began putting together a naval bombardment plan on June 15.

While planning went forward, a late June storm raged in the English Channel, scattering Deyo's task force out to open sea and into British ports; they reassembled in Portland Harbour, Dorset.

An army liaison officer aboard USS Tuscaloosa representing General "Lightning Joe" Collins (VII Corps) expedited communications between different services and commands.

[3] To support the Allied advance over the Cotentin Peninsula and their planned assault on the German fortifications, on June 25, 1944, a bombarding force (CTF 129, Twelfth Fleet) was organized under the command of Rear Admiral Morton Deyo, USN.

The navy was additionally tasked to coordinate with the army air force bombers to interdict ammunition resupply and, as infantry closed, follow direction from spotter planes.

[5] Rear Admiral Carleton Fanton Bryant's smaller Battle Group 2 was assigned "Target 2", the Battery Hamburg, which was located near Fermanville, inland from Cape Levi, 6 mi (9.7 km) east of Cherbourg.

Channel “L” was extended beyond the extent used for D-Day landings along east and north coasts of Cherbourg to protect Task Force 129 closing in for bombardment.

[10] As a result of pre-bombardment concerns by ground commanders, all planned long-range shots on seaward batteries were cancelled and it was decided that only call fires would be delivered.

Collins, commanding VII Corps, arranged for shore fire control parties to join infantry units as they approached German fortified objectives.

[11] During the Normandy landings the standard operating procedure for "shore fire control parties" (SFCP) called for nine per infantry division.

As noon passed at eight bells, the task force plodded towards the in-shore fire support areas at the minesweepers’ five-knot (9 km/h; 6 mph) speed.

German salvos from a village three miles (4.8 km) west of Cherbourg at Querqueville began falling among the deployed minesweeper flotillas.

The helmsman of the ship, a 21-year-old quartermaster, 3rd Class Christen Norman Christensen, was centered directly below the blast and was killed, the first and last combat fatality to occur on board.

German shore batteries were in turn laying well placed fire, churning the seas with near misses bracketing Deyo's ships.

After an inspection of the port defenses, an army liaison officer reported that the guns that had been targeted could not be reactivated, and those that could have been turned landward were still pointed out to sea when the city had fallen.

The Allied Supreme Commander, General Dwight D. Eisenhower later wrote, "the final assault was materially assisted by heavy and accurate naval gunfire."

Von Schlieben reported to Generalfeldmarschall Erwin Rommel that further resistance had been useless due in part to "heavy fire from the sea", while Admiral Theodor Krancke recorded for his war diary, that one of the contributing causes to Cherbourg's fall was a "naval bombardment of a hitherto unequalled fierceness.

According to these reports, the Allied naval fire curtain was one of their trump cards and in a crisis, it was more accurate and it could be sustained on target, fulfilling the role of a floating artillery arm.

The reports go on to compare a cruiser to a regiment of artillery and state that battleships with 38 to 40 cm guns had no equal in land warfare, and could only be matched "by an unusual concentration of very heavy batteries".

[19] The German report said that Allied troops had a "particular advantage" from ship formations that provided the mobility to concentrate artillery on any point on the battlefield, and then change their placement to whatever the fighting required.

He added that they were skillfully directed by air and ground spotters, and that the Allied naval gunnery had a high rapid-fire capacity at range.

According to Admiral Bertram Ramsay, Naval Commander in Chief of the Allied Naval Expeditionary Force, if the German gunners had not been hampered by faulty ammunition, "they might well have inflicted heavy damage to ...[the Allied] ...ships at the relatively close range ..." Prior to June 1944, the United States Navy's main experiences in the war had been in the Mediterranean and the Pacific.

According to naval historian Samuel Morison, these experiences had resulted in an assumption that the modern fire control systems on U.S. ships allowed them to close with and defeat coastal batteries at will.

"[18] Deyo's after-action report recommended that long-range bombardment with plane spotting would be required to silence casemated batteries, stating that either good air spot or shore parties are required for effective naval bombardment, especially when strong currents add to the navigational problems of a task force under accurate shore battery fire.