Former Defense Secretary Chuck Hagel on Tuesday urged caution in response to NATO’s plans to deploy four battalions to the Baltic states, warning it could lead to another Cold War with Russia.

“If I were secretary of defense today, I’d be careful with this because, I’m not opposed to it, but we can find ourselves very quickly in another Cold War buildup here, that really makes no sense for either side,” he said at a media roundtable at the Atlantic Council.

In response to NATO’s decision to send the four battalions — two American, one British and one German, Moscow quickly responded that it would send 30,000 Russian troops along its western and southern borders.

“Then we continue to build up the eastern flank of NATO, with more battalions, more exercises, and more ships and more platforms, and the Russians will respond. I’m not sure where that takes you either,” he said.

“I’m not sure there’s some real strategic thinking here,” he added.

Hagel has previously criticized the White House for reacting to crises, versus dealing with them strategically. He served as Obama’s third defense secretary, but resigned after butting heads with members of the National Security Council.

“It’s a reaction, it’s a tactical ricocheting from crisis-to-crisis, which I think has been much of what we think we have strategically in the Middle East, with ISIS in particular,” he said.

And he added, when you deploy troops, “There’s always going to be increase.”

Damon Wilson, executive vice president of the Atlantic Council, pushed back against the idea that taking steps to deter Russia is provocative, but said “what becomes dangerous is if we project and telegraph too frequently our ambivalence.”

Wilson, who was also former special assistant to the president and senior director for European Affairs at the National Security Council, said Russia looks for “windows of opportunities and vulnerabilities” and NATO’s strategy should be to make clear “there is no vulnerability in the Baltic States, there’s no vulnerability on the alliance turf.”

Dr. Frances Burwell, vice president of the Atlantic Council’s European Union and Special Initiatives, cautioned against underestimating Putin based on Russia’s flagging economy.

“Don’t confused the overall Russian economy with what Putin needs to stay in power. His incentive is to preserve the economy that his cronies benefit from, not the whole economy,” she said.

“And when you’re dealing with the public, a little bit of economic stress if you can blame it on outsiders like the Europeans or us, is actually good for staying in power, and keeping loyalty, so the incentives are a bit reversed from what we all commonly think of them.”