Donald Trump Tweets Insults To Obama Following Rutgers Speech

The only question was, how long would it take for Donald Trump to respond?

On Monday, Trump fired back at President Obama's Rutgers speech that took veiled shots at the presumptive Republican nominee for president.

And the billionaire reality T.V. star used his favorite platform - Twitter - to make his voice heard.

In the much-talked-about speech, President Obama called on graduates of Rutgers University Sunday to take on their "shared challenges" and fight back against some of rhetoric of the 2016 presidential campaign.

He didn't mention his name, but he did criticize the language of the presumptive Republican nominee, Donald Trump, saying: "It's not cool to not know what you're talking about."

"That's not challenging political correctness," he said, saying some have become too "confident in our ignorance."

"There are a whole lot of folks who are book smart but have no common sense," he said.

Trump took particular aim at this quote:

"You may wonder where this strain of anti-intellectualism came from," he said. "In politics and in life, ignorance is not a virtue."

Read more: WATCH: Obama Speaks At Rutgers University, Takes Shots At Donald Trump

Obama, whose appearance at Rutgers University's 250th commencement was the first time a sitting president has spoken at the college, took aim at Trump's call to block Muslims from entering the United States, saying the idea "contradicts the evidence that our growth, our innovation" boosted America because of immigration.

"That's how we became America," he said.

Obama also ripped Trump's idea to build a wall along the U.S. border with Mexico, saying the "biggest challenges cannot be solved in isolation."

Trump has criticized Obama for several years, questioning whether he was really born in Hawaii and if his birth certificate was authentic. His questioning led to the beginning of what's known as the "birther" movement.

Obama also mocked politicians who expressed skepticism of climate change, noting that a United States senator once brought a snowball to Congress "as proof" that the scientific phenomenon doesn't exist.

He said "imagine if your fifth-grade science teacher" had seen that. "He'd get a D."