A stunning market comeback occurred after fear over Russian aggression subsided, according to Jim Cramer's analysis.

• On Thursday, CNBC's Jim Cramer explained why the U.S. stock market recovered from an initial decline due to Russia's invasion of Ukraine.
• The "Mad Money" host stated that Russia's invasion of Ukraine was foreseeable, as the government had been issuing warnings on a daily basis for some time now. This was one of the reasons for the recent sell-off.

Jim Cramer on CNBC explained the reasons for Wall Street's sudden turnaround on Thursday, as the major U.S. stock indexes recovered from significant losses due to Russia's invasion of Ukraine and ended the day in the positive.

"Our government has been warning us about Russia invading Ukraine for many weeks, and it's one of the reasons we sold off so hard in the last few weeks. The only surprise is that we still can't be sure how the war is going," said the "Mad Money" host.

After weeks of speculation about a possible invasion, Russia launched an air, land, and naval attack on Ukraine. The ongoing conflict may complicate an economic recovery already hindered by surging inflation and supply chain snarls, including the production of semiconductor chips, which both Russia and Ukraine play key roles in.

On Thursday, the U.S. stock market demonstrated strength and rebounded after a significant decline earlier in the day. The gained 1.5% after falling more than 2.6%, while the increased by approximately 3.3% after being down almost 3.5% at one point. The surged around 92 points after dropping 859 points earlier in the session.

The pan-European equity index and other major European indexes ended their sessions on Thursday with significant losses, with the pan-European index dropping over 3%.

Cramer stated that the U.S. market has remained stable due to strong consumer spending and a healthy job market. However, buyers may be disregarding Russia's attack because they believe President Biden's promise to impose broader economic sanctions on Russia is unlikely to be fulfilled, according to Cramer.

Cramer acknowledged that the buyers could be incorrect, but their assumption that the government would not produce munitions for mechanized troops and face massive partisan resistance was not taken into account. However, at present, buyers are betting that these scenarios are unlikely to occur.

Although there is uncertainty, Cramer stated that investors should not sell off their portfolios.

"I could play it like most commentators I have heard all day and yesterday: 'just sell everything' ... I'll leave that to everyone else" and look for buying opportunities instead, he said.

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