Sen. Joni Ernst (R-IA) told Neil Cavuto that President Obama's delay in ordering all flags be flown at half-staff at the White House and at U.S. federal buildings in honor of the Chattanooga attack victims is "inexcusable."

Obama has faced days of criticism for not immediately ordering the flags to be lowered after the attack happened. 

Fox News reported:

In a proclamation issued early Tuesday afternoon, Obama said of the Chattanooga victims, "We honor their service. We offer our gratitude to the police officers and first responders who stopped the rampage and saved lives. We draw strength from yet another American community that has come together with an unmistakable message to those who would try and do us harm: We do not give in to fear. You cannot divide us. And you will not change our way of life."

He ordered flags flown at half-staff at the White House and "all public buildings and grounds," as well as over military posts and naval stations and vessels -- until July 25. Flags will be flown at half-staff at U.S. embassies and other overseas diplomatic offices.

Four Marines - Gunnery Sgt. Thomas Sullivan, Lance Cpl. Skip Wells, Sgt. Carson Holmquist and Staff Sgt. David Wyatt - and Navy Petty Officer 2nd Class Randall Smith were killed in the shootings at two military centers.

Ernst said that she applauds Sen. Mitch McConnell (R-KY) for lowering the flags at the U.S. Capitol building.

"I think we need to honor those that lost their lives in Chattanooga," she stated. "The president's reaction was a little bit delayed, and that's inexcusable."

Ernst also said that she wants to see a "definitive plan" for how the country is going to defeat ISIS.

"We have not seen that coming from our administration," she asserted. "I would love to see a definitive plan, not only how we are going to degrade ISIS, but how we are going to defeat them ... Right now our administration is not showing that leadership."

Watch the "Your World" segment above.

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