It’s not been easy to pin down President Trump’s position on gun control in the wake of the Florida shooting. In the same chain of tweets on Thursday in which he backed arming some schoolteachers, Trump also said he will be “strongly pushing” for stricter gun laws, including fuller background checks that focus on mental health, as well as raising the age for gun purchase to 21 and ending the sale of “bump stocks”—devices which allow rifles to shoot hundreds of rounds per minute. The president urged Congress to back him and “finally do something on this issue.” Trump tweeted Thursday morning: “I will be strongly pushing Comprehensive Background Checks with an emphasis on Mental Health. Raise age to 21 and end sale of Bump Stocks! Congress is in a mood to finally do something on this issue - I hope!”