PHILADELPHIA (CBSNewYork/AP) -- Republican Donald Trump unveiled a plan to boost military spending by tens of billions of dollars on Wednesday, promising major increases in the number of active troops, Navy ships and submarines, and fighter planes as he works to convince skeptics in both parties that he's ready to lead the world's most powerful military.

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The New York businessman, who has struggled at times to demonstrate a command of foreign policy, also seemed to acknowledge he does not currently have a plan to address cyber security or the Islamic State of Iraq and Syria.

If elected, Trump said he would give military leaders 30 days to formulate a plan to defeat the group, commonly known as ISIS. And he would ask the joint chiefs of staff to conduct a review of the nation's cyber defenses to determine all vulnerabilities.

Trump's address came hours before his national security acumen is tested at a "commander in chief'' forum on NBC.

"We want to defer, avoid and prevent conflict through our unquestioned military strength,'' Trump declared of his Democratic opponent in his Wednesday speech, delivered inside the exclusive Union League of Philadelphia, which first allowed women in 1986.

CBS2's Alice Gainer reported Trump wants an active Army of around 540,000; a Marine Corps based on 36 battalions; a Navy approaching 350 ships and submarines; and and Air Force of at least 1,200 fighter planes.

Trump said it will be partially paid for through unspecified common-sense reforms.

"That will eliminate government waste and budget gimmicks and that protect hard-earned benefits," Trump said. "The military will not be exempt, either. The military bureaucracy will have to be trimmed down."

Trump also wants to ask countries like Germany, Japan and Saudi Arabia to pay more for the security the U.S. provides them.

He also called Hillary Clinton "trigger-happy and very unstable.

The appearances mark an intense, two-day focus on national security by Trump, who has offered tough rhetoric on America's challenges abroad but few details.

The United States currently spends more than $600 billion a year on the military, more than the next seven countries combined.

Clinton has tried to paint the billionaire businessman as erratic, making the case that his disposition would be a major liability on the world stage.

"They know they can count on me to be the kind of commander in chief who will protect our country and our troops, and they know they cannot count on Donald Trump,'' Clinton said Tuesday. "They view him as a danger and a risk.''

Clinton's campaign says she now has 95 retired generals and admirals backing her. Meantime, Trump's team announced Tuesday he had a list of 88.

Trump's team has worked aggressively in recent days to turn deflect such criticism back at Clinton.

During the national security forum in New York City Wednesday evening, Trump and Clinton won't be on stage at the same time.

The audience will be made up of mostly military veterans and active service members who will get to ask questions.

As CBS2's Dick Brennan reported, a recent CNN poll showed Trump topping Clinton 45 to 43 percent among likely voters. Libertarian Gary Johnson came in at 7 percent and the Green Party's Jill Stein at 2 percent.

(TM and © Copyright 2016 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2016 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)