The prospect of a U.S. attack on Iran has roiled oil prices this year, but analysts tell CNBC a strike would require more military commitment and be more complicated, than the U.S. is prepared for.

Tensions are high, and despite talks last week in Oman, both sides remain at an impasse. U.S. President Donald Trump’s pressure on the Iranian regime escalated after a brutal crackdown on anti-government protestors across the country last month.

Trump said this week he was considering sending a second aircraft carrier to the Middle East, even as Washington and Tehran prepare to resume talks. On Tuesday, he threatened Iran with “something very tough,” if it does not agree to Washington’s demands, which range from halting the country’s nuclear enrichment to cutting Tehran’s ballistic missile program.

The U.S. deployed the USS Abraham Lincoln carrier strike group to the Middle East in January. This brought the number of missile destroyers in the region to six, but, analysts say, this still wouldn’t be enough to topple the regime. Following through on his “something tough” threat would mean a prolonged conflict in a region Trump is wary of.

“U.S. forces in the region are not adequate to support a significant long-term military operation in Iran which would be necessary to achieve any major military objective,” Alireza Ahmadi, executive fellow at the Geneva Center for Security Policy, told CNBC.