WASHINGTON—Sen. Ted Cruz tied his rival Donald Trump to President Barack Obama in response to the Islamic terrorist attacks in Brussels, Belgium, Tuesday.

Monday, Trump called for the United States to pull back America’s involvement with the North Atlantic Treaty Organization (NATO), a military alliance of countries from North America and Europe (originally western Europe) against common threats.

When NATO was founded in 1949, the chief threat it was designed to protect against was the Soviet Union. But the treaty members’ mutual-defense obligations are against all common threats, with the principle that “an attack on one is an attack on all.”

When asked if America should “rethink” its “involvement in NATO,” the billionaire began his answer to CNN’s Wolf Blitzer with, “Yes, because it’s costing us too much money.”

Tuesday, Cruz began his short press conference by saying:

It’s striking that the day after Donald Trump called for America weakening NATO, withdrawing from NATO, that we see Brussels, where NATO is headquartered, the subject of a radical Islamic terrorist attack. Donald Trump is wrong that America should withdraw from the world and abandon our allies. Donald Trump is wrong that America should retreat from Europe, retreat from NATO, hand [Russian President Vladimir] Putin a major victory, and while he’s at it, hand ISIS a major victory.

In response to a reporter’s question, Cruz tied Trump to Obama, answering:

NATO should join with the United States in utterly destroying ISIS. And I would note that NATO is ready to act in a way that our president is not. Donald Trump’s proposal to withdraw from the world, to withdraw from NATO, to withdraw from Europe is sadly consistent with his statement that he intends to be neutral between Israel and the Palestinians. We have seen for seven years a president that cannot distinguish between our friends and our enemies—a president that cannot distinguish between the nation of Israel and Islamic terrorists who seek to murder us. And it would be a mistake to elect another president who buys into the same left-wing moral relativism that equates the terrorist blowing himself up and murdering innocent civilians to the brave soldiers and law enforcement officers risking everything to keep us safe.

Focusing briefly on the current occupant of the White House, who is on an official visit to Havana with Cuba’s communist dictator, Raul Castro, Cruz—whose father fled Cuba as a young man to escape political persecution—sharply criticized Obama. “While our friends and allies are attacked by radical Islamic terrorists, President Obama is spending his time going to baseball games with the Castros,” he said.

The senator called on Obama either to immediately return to the White House to personally take charge of the U.S. response to the Brussels terrorist attack or to announce that he was heading immediately to Brussels to meet with our NATO allies.

Further comparing Trump with Obama, Cruz continued, “And I would note that retreat from the world—that Obama-Clinton retreat from the world—is very much the retreat from the world that Donald Trump is advocating.”

But the Texas senator then contrasted Trump from Obama, finishing his answer by adding that “even Barack Obama hasn’t gone so far as arguing for withdrawing from NATO.”

Cruz concluded his press conference by declaring, “The way to respond to terrorist attacks is not weakness—is not unilateral and preemptive surrender. Abandoning Europe, withdrawing from NATO as Trump suggests, is preemptive surrender.”

Ken Klukowski is legal editor for Breitbart News. Follow him on Twitter @kenklukowski.