>> Peace through strength.>> Donald Trump on Wednesday, appealing directly to voters unsure if he should ever command US forces. In his most detailed national security speech, Trump pledging a vast US military buildup with hundreds more ships and planes.>> We want to deter, avoid and prevent conflict through our unquestioned military strength.
>> Campaign reporter, Emily Stevenson.>> Trump's argument for a long time has been that the military is getting depleted. That we're using old planes, old ships. That our allies think that we're weaker, and that our adversaries think that they can stand up to us because we are not as impressive as a military as we used to be.
He's doing that as a way to combat this idea that he doesn't have the expertise. And also, he's trying to push back on Hillary Clinton's criticism of him that he doesn't have the temperament to be the commander in chief. He's been talking about that for a long time.
>> We have the greatest people in the world.>> The New York mogul also promising thousands more combat troops and a quote, state of the art missile defense system. Claiming, President Obama had pushed a smaller military and that Hillary Clinton would do the same.>> Really, we will have aggression like you've never seen before.
And you've got it already happening.>> Trump working against an outright rejection by many national security leaders, including Republicans, who have called him unfit to be commander in chief. With former defense secretary, William Cohen becoming the latest on Wednesday.>> We will rebuild our military.>>
>> Trump offered no clear idea where the billions of dollars would come from for his plan.
But said, he would lift limits on spending, known as the sequester aimed at reigning in the nation's massive deficits.