The United Arab Emirates said Thursday it would join a U.S.-led maritime coalition aimed at protecting international shipping in and near the Strait of Hormuz following alleged Iranian attacks on oil tankers there.

The UAE joins neighbors Saudi Arabia and Bahrain, along with the United Kingdom and Australia in the effort to protect vessels in the Gulf of Oman, the Persian Gulf and the narrow Strait of Hormuz waterway that separates them and which acts as a transit point for a fifth of the world's oil exports.

On Sept. 14, a major Saudi oil processing plant was rocked by a series of explosions. The facility, and another oil field to the south, had been attacked from the air. Here's what we know — at this time — about the attacks based on physical evidence.

The strike was large and sophisticated

America's best-known obelisk reopens to the public on Thursday after more than three years of construction on a new security facility and renovations to its elevator system.

The Washington Monument will again welcome visitors up to its observation deck, where, from more than 500 feet in the air, visitors can see national landmarks including the U.S. Capitol, Washington National Cathedral, Ronald Reagan Washington National Airport, the Lincoln Memorial and the Jefferson Memorial.

But first, you have to go through security.

Emergency sirens wailed on Hawaii's Oahu and Maui islands Wednesday evening, warning of a tsunami, but the alert turned out to be a mistake, sparking anger from residents who recalled a similar false warning last year of an imminent ballistic missile attack.

Within minutes of the alarm going off shortly after 5 p.m. local time (11 p.m. ET) authorities were trying to calm the public by getting out word of the mistake.

House Speaker Nancy Pelosi, D-Calif., will introduce Thursday her long-anticipated plan to lower the cost of prescription drugs. It is a priority shared by President Trump, fueling a glimmer of hope that there is a deal to be had on the issue ahead of the 2020 elections.